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5551.

(a) Show that for every nutural number n relatively prime to 10, there is another natural number m all of whose digits are 1 's such that n divides m. (b) Hence or otherwise show that every positive rational number can be expressed in the form (a)/(10^(b)(10^(c)-1)) for some natural a, b, c.

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Solution :(a) Divide the n+1 number 1, 11, 111, ....,111,....1 (All having only 1 as digits ) by n. Among the n+1 remainders so obtained, two must be equal as the possibilities for remainders are 0, 1, 2,....., n-1 which are n in number. Thus there must be two number x=11.... and y=11.....1 having say j digits and k digits respectively which LEAVE the same remainders after DIVISION by n. We may take `j lt k`. Now we see that y-x is divisible by n. But y-x = 11....100 ... 0 where there are k - j number of 1's and remaining zeros. Since n is COPRIME to 10, we see that n divides m=11 ... 1, a number having only 1's as its digits.
(b) If p/q is any rational number `(p gt 0, q gt0)`, then we may write `q=2^(r)5^(s)t`, where t is coprime to 10.
Choose a number m having only 1's as its digits and is divisible by t. Consider 9m, Which has only 9 as its digits and is still divisible by t. Let k=9 m/t. We see that,
`qk=9m2^(r)5^(s)=(10^(@)-1)2^(r)5^(s)`,
where c is the number of digits in m. Hence we can find d such that `qd=10^(b)(10^(c)-1)` multiply by a suitable power of 2 if `s gt r` and by a suitable power of 5 if `r gt s`). Then
`(p)/(q)=(pq)/(qd)=(a)/(a0^(b)(10^(c)-1))`
where a=pd.
5552.

Find the transpose of each of each of the following matrics: [[1,2],[-1,3]]

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SOLUTION :`[[1,2], [-2,3]]`
5553.

If I_(n) = int (log x)^(n) dx then I_(6)+ 6I_(5) =

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`X(logx)^(5) + c`
`- x(LOG x)^(5)+ c`
`x (log x)^(6) + c`
`- x(log x)^(6)+ c`

ANSWER :C
5554.

Vertex is (4, 3) and diretctrix is 3x+2y-7=0 then equation of latusrectum is

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3x+2y-18 =0
3x+2y-29 = 0
3x+2y-8 = 0
3x+2y-31 =0

Answer :B
5555.

Let K is a positive Integer such that 36 +K , 300 + K , 596 + K are the squares of teree consecutive terms of an arithmetic progression. Find K.

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ANSWER :925
5556.

A species has an initial population 4^(10). At the end of first day, the population increases by 50%. At the end of second day, it decreases by the same percentage. Days for the population to reach 3^(10) is

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10
20
50
100

Answer :B
5557.

Discuss the continuity of the function f, where f is defined by f(x)={{:(2x," if "x lt 0),(0," if "0 le x le 1),(4x," if "x gt 1):}.

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ANSWER :x=1 is the only POINT of DISCONTINUITY.
5558.

Let A={1,2,3} and Let R={(1,1),(2,2),(3,3),(1,3),(3,2),(1,2)} then R is

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REFLEXIVE and SYMMETRIC but TRANSITIVE
Reflexive and transitive but not symmetric
symmetric and transitive but not reflexive
An EQUIVALENCE relation

Answer :B
5559.

Consider the equation E_(1):vecr xx (2hati-hatj+3hatk)=3hati+hatk and E_(2): vecr xx (hati+2hatj-3hatk)=2hati-hatj, hten

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`E_(1)` represents a line
`E_(1)` represents two parallel LINES
`E_(2)` represents a line
`E_(2)` represents two parallelplanes

Solution :`E_(1): vecr xx (2hati-HATJ+3hatk)=3hati+hatk`
`rArr 3hati(3y+z)-hatj(3x-2z)+hatk(-x-2y)=3hati+hatk`
`therefore 3y+z=3, 3x-2y=0, -x-2y=1`
From first two EQUATIONS, `3x-2(3-3y)=0`
`rArr 3x+6y=6 rArr x+2y=2`
Now, `x+2y=-1, x+2y=2` are parallel planes.
`E_(2): vecr xx (hati+2hatj-3hatk)=2hati-hatj`
`rArr hati(-3y-2z)-hatj(-3x-z)+hatk(2x-y)=2hati-hatj`
`therefore hati(-3y-2z)-hatj(-3x-z)+hatk(2x-y)=2hati-hatj`
`therefore -3y-2z=2, 3x+z=-1, 2x-y=0`
i.e., `-6x-2z=2, 3x+z=-1`
`therefore` Straight line, `2x-y=0, 3x+z=-1`
5560.

If a 679b is a five digit number that is divisible by 72, then a+b is equal to

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ANSWER :C
5561.

There are 5 copies each of 4 different books. Find the number of ways of arranging these books in a shelf.

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ANSWER :`(LFLOOR20)/((lfloor5)^4)`
5562.

Let A and B be two sub-sets of R x R, defined as follows: A = {(a,b) : a,b in R " and " tan^(-1)a + cot^(-1)b = pi/2} and B={(a,b) : a,b in R " and " sin^(2) a + cos^(2)b =1}, then

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`A CAP B = {{a,a) : a in R}`
`A cap B = phi`
`A CUP B = R xx R`
`A cup B = {(a,a), a in R}`

ANSWER :A
5563.

If for a Binomial distribution, mu=10 and sigma^(2)=5, then find P(X gt 6).

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Answer :`(1)/(20^(20))sum_(r = 7)^(20)""^(20)C_(r)`
5564.

S and S^(1) foci of an ellipse. B is one end of the minor axis. If I.SBS^(1) is a right angled isoscles triangle, then e =

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PARALLELGRAM
RHOMBUS
square
rectangle

Answer :C
5565.

The partial fractions of (x^(2)+1)/(x(x^(2)-1)) are

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`(1)/(X)-(1)/(x+1)+(1)/(x-1)`
`-(1)/(x)+(1)/(x+1)+(1)/(x-1)`
`1/x - (1)/(x+1)+(1)/(x-1)`
`1/x + (1)/(x+1)-(1)/(x-1)`

ANSWER :B
5566.

Find the static moment of the upper portion of the ellipse (x^(2))/(a^(2)) + (y^(2))/(b^(2))=1 about the x-axis.

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ANSWER :1
5567.

MatricesA and B are givenbelow.FindA+B,B+A,A-BandB -A Verify that A+B=B+A and B-A=-(A-B).A=[{:(7),(1):}]B=[{:(-6),(9):}]

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SOLUTION :`A+B =[[1],[10]],B+A=[[1],[10]]`
`A-B=[[13],[-8]],B-A=[[-13],[8]]`
`:. A+B=B+A "and" B-A =-(A-B)`
5568.

n is a natural number. It is given that (n +20) + (n +21) + ......+ (n + 100) is a perfect square. Then the least value of n is "___________"

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ANSWER :4
5569.

Find the eccentricity, foci, length of latusrectum and the equations to thedirectrices of the hyperbola(x^(2))/(16)-(y^(2))/(9) = 1

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Answer :`E=(sqrt(7))/(4)` foci, `(+- 2,sqrt(3))`,length of LATUS RECTUM =9
EQUATION of directrix `x sqrt(7)+32=0`
5570.

Find the eccentricity, co ordinates of foci-length of latus rectum and equation of directrices of the folloeing ellipses. 9x^2+16y^2-36x+32y-92=0

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Answer :`e=(SQRT(7))/(4)` foci `(2+- sqrt(7)-1)`,
Length of latus RECTUM =9/2. , Equation to DIRECTION `sqrt(7)=2 sqrt(7)+-16`
5571.

If Lim_(xto oo) "sin"((pi(1-cos^(m)x))/(x^(n))) exists and non-zero where m,n in N then

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m=1 , n=1
m=1 , n=2
m=2 , n=2
m=3 , n=2

Solution :When m=1, n=1
`UNDERSET(NTO oo)Lim"SIN"((pi(1-cosx))/(x))=sin0=0`
When m=1 , n=2
`underset(nto oo)Lim"sin"((pi(1-cosx))/(x^(2)))=sin(pi//2)=1`
When m=n=2
`underset(nto oo)Lim"sin"((pi(1-cos^(2)x))/(x^(2)))=underset(nto oo)Lim"sin"((pi(1-cosx)(1+cosx))/(x^(2)))=sin(pi)=0`
When m=3 , n=2
`underset(nto oo)Lim"sin"((pi(1-cos^(3)x))/(x^(2)))=underset(nto oo)Lim"sin"((pi(1-cosx)(1+cos^(2)x+cosx))/(x^(2)))=sin((3PI)/(2))=-1`
5572.

Find the equation of the circle with centre C and redius r where. C = (a,-b),r=a+b

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ANSWER :`X ^(2) + y^(2) -2ax +2by-2ab =0 `
5573.

Letf (x)=[x]andg (x )=|x| ,AAxin Rthen valueofgof (( - 5 ) /(3))+fog((- 5)/(3))isequal to:( wheref _0 g (x)=f (g (x))).

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` 1 `
` - 1 `
` - 2 `
` 3 `

SOLUTION :`f(X) = [x], g (x) = |X|`
`g(f(x)) + f(g(x))`
`= |[x]| + |[x]|`
`= |[(-5)/(3)]| + [|(-5)/(3)|]`
` = |-2| + [(5)/(3)] = 2 + 1 = 3`
5574.

An equilateral triangle is of side 10 units. In measuring the side, an error of 0.05 units is made. Then the percentage error in the area of the triangle is

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5
4
1
0.5

Answer :C
5575.

Sum of solution of the equation |{:(1,2,x),(2,3,x^2),(3,5,2):}|=10is :

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1
`-1`
2
4

Answer :B
5576.

If f(x) =[|x|]where[.]denotesthegreatestintergerfunction , then whichof thefollowingis not true?

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f(X)is continuous`AA x in R`
f(x)is continuousfromrightand discontinuousfromleft `AA s in N`
f(x) is conttinuousfromrightleftanddiscontinuous from RIGHT`AA x in I`
f(X)is continuousat x=0

Answer :B::D
5577.

Choose the correct answer. Let veca"and"vecb be two unit vectors and theta be the angle between them.Thenveca+vecb is a unit vector,if:a)theta=pi/4b)theta=pi/3c)theta=pi/2d)theta=(2pi)/3

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`THETA=pi/4`
`theta=pi/3`
`theta=pi/2`
`theta=(2PI)/3`

ANSWER :D
5578.

If f(x)=|cosx-sinx|," then "f^(1)(pi/6) is equal to

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1)`-1/2(1+sqrt3)`
2)`1/2(1+sqrt3)`
3)`-1/2(1-sqrt3)`
4)`1/2(1-sqrt3)`

ANSWER :A
5579.

By using the properties of definite integrals, evaluate the integrals int_(0)^(pi/2)(2log sin x - log sin 2x)dx

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ANSWER :`pi/2log1/2`
5580.

If order of matrix A is 2X3 and order of matrix B is 3X5 then order of matrix B'A' is :

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5X2
2X5
5X3
3X2

Answer :A
5581.

Find the values of a,b if ax^(2) + bxy+ 3y^(2) -5x +2y -3 = 0represents a circle . Also find the radius and centre of the circle .

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Answer :a=3,b =0 radius = ` (SQRT(65))/( 6), ( ( 5)/(6), (-1)/(3)) `
5582.

Find the sum of the infinite series (7)/(5)(1+(1)/(10^(2))+(1.3)/(1.2).(1)/(10^(4))+(1.3.5)/(1.2.3).(1)/(10^(6))+....)

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SOLUTION :N/A
5583.

Which of the following statement(s) is//are correct

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Mass of one ca atom is `6.64xx10^(-23) g`
Volume of 18 g `H_(2)O` at 1 atm pressure and 273 K temperature is 22.4 L
Number of oxygen atoms in
`C_(4)H_(6)O_(2)` sample is 2, if this sample has 6 g atom hydrogen

ANSWER :A
5584.

If the points with position vectors 10hati+3hatj, 12hati-5hatj and ahati+11hatj are collinear, find the value of a.

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SOLUTION :LET the points are A,B and C.
As A,B and C are co-llinear.
We have `VEC(AB)` = `vec(AC)`
`vec(AB)` = `lambdavec(AC)`
`IMPLIES (12i-5j)-(10i+3)
= `lambda[(ai+11j)-(10i+3j)]`
`implies` 2i-8j = `(a-10)lambdai+8lambdaj`
Comparing the components we have
`8lambda`= -8 `implies lambda` = -1(a-10)(-1) = 2
`implies` -a+10 = 2
`implies` a= 8.
5585.

Find the equation of all lines having slope 2 which are tangents to the curve y=(1)/(x-3) , x ne 3 .

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ANSWER :No TANGENT to the CURVE which has SLOPE 2.
5586.

The value of int_(0)^(1) (xdx)/( (x^(2) +1)^(2) ) is

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`1/2`
`1`
`1/3`
`1/4`

ANSWER :D
5587.

Let f(x)=|{:(,1//x,logx,x^(n)),(,1,-1//n,(-1)^(n)),(,1,a,a^(2)):}| where ("where"f^(n)(x) "donotes "n^(th)derivative of f(x).

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`F^(N)(1)"is indepent of a"`
`f^(n)(1)"is indepent of n"`
`f^(n)(1)"is indepent a of n"`
`y=a(x-f^(n)(1))` represent a straight LINE through the origin

Answer :A::B::D
5588.

The number of ways that 3 English, 3 Hindi & 3 Telugu books can be chosen from a shelf containing 5 English, 4 Hindi and 3 Telugu books is

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10
20
40
60

Answer :C
5589.

Two this slabs ................

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SOLUTION :
From the given vectors for the direction of LIGHT RAYS we can use For the first medium `SIN theta_(1)=a/SQRT(a^(2)+b^(2))`
and for the second medium `sin theta_(2)= c/sqrt(c^(2)+d^(2))`
By snell's law, we have `mu_(1) sin theta_(1) = mu_(2) sin theta_(2)`
`implies (mu_(1) a)/sqrt(a^(2)+b^(2))=(mu_(2) c)/sqrt(c^(2)+d^(2))`.
5590.

Letf(x): R to Rb " and "g (x)=x-7, x in R". Find"(f o g) (7)

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SOLUTION :(fog )(7) =f{G(7)}=f(7-7) =f(0) =(0+7)=7
5591.

vec(u),vec(v) and vec(w) are not co-planar vectors and p and q are real numbers. If [3vec(u),p vec(v),p vec(w)]-[p vec(v),vec(w),q vec(u)]-[2vec(w),q vec(v),q vec(u)]=0 then ……………

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(p, q) has only TWO VALUES.
(p, q) has more than two values. But not all the values.
(p . q) has all the values.
`(p.q)` has only ONE VALUE.

ANSWER :B
5592.

The maximum value of |3z + 9 - 7i| if |z + 2- i| = 5 is

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10
15
20
5

Answer :C
5593.

x^2+y^2+2lambdax+5=0 and x^2+y^2+2lambday+5=0 are two circles. P is a point on the line x-y=0. If PA and PB are the lengths of the tangents from P to the two cricles and PA=3, thenPB=

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1
3
8
5

Answer :B
5594.

Let f (x) be a function which satisfy the equatio f (xy) = f9x) + f(y) for all x gt 0, y gt 0 such that f '(1) =2. Let A be the area of the region bounded by the curves y =f (x), y = |x ^(3) -6x ^(2)+11 x-6| and x=0, then find value of(28)/(17)A.

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ANSWER :7
5595.

The locus of z satisfying the |(x+2i)/(2z+i)| lt 1, inequality where z=x+iy, is

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`x^(2)+y^(2) LT 1`
`x^(2)-y^(2) lt 1`
`x^(2)+y^(2) GT 1`
`2X^(2)+3Y^(2) lt 1`

5596.

f(x) and g(x)are polynomicalof degree 2 such that |int_(a_(1))^(a_(2))(f(x) - 1)dx|=|int_(b_(1))^(b_(2))(g(x)-1)dx| where a_(1), a_(2)(a_(2) gt a_(1)) are rootsof equation f(x) = 1 and b_(1), b_(2)(b_(2) gt b_(1)) are roots of equation g(x) = 1. If f"(x) and g"(x) are positive constant and |int_(a_(1))^(a_(2))f((x))dx|=(a_(2)-a_(1))-|int_(b_(1))^(b_(2))(f(x)-1)dx| but |int_(b_(1))^(b_(2))(g(x))dx|ne(b_(2) -b_(1))-|int_(b_(1))^(b_(2))(g(x)-1)dx|then

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`|f"(X)|lt |G"(x)|`
`|f"(x)|gt|g"(x)|`
`a_(2)-a_(1)gt b_(2) - b_(1)`
`a_(2) - a_(1) gt b_(2) - b_(1)`

Solution :N//A
5597.

Suppose A and B are events with P(A)=0.5, P(B)=0.4 and P(AcapB)=0.3. Find the probability that i) A does not occur, ii) neither A nor B occurs.

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ANSWER :0.5 ; 0.4
5598.

Let f and g be increasing and decreasing functions respectively from [0,oo) to [0, oo), Let h(x)=f(g(x)). If h(0)=0, then h(x)-h(1) is :

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LESS than - H(1)
ALWAYS +ve
always -ve
STRICTLY increasing.

Answer :A
5599.

f:NxxNrarrN , f("(m,n)")=m+n . If f one one and onto ?

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SOLUTION :N/A
5600.

Each of graph drawn has same initial and final of velocity over same time interval :- Which of the following statements is TRUE ?

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Average VELOCITY is same for all the particle
Average ACCELERATION is same for all the particles
Displacement is same for all particles
DISTANCE travelled is same for all particles