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This section includes InterviewSolutions, each offering curated multiple-choice questions to sharpen your knowledge and support exam preparation. Choose a topic below to get started.
| 28551. |
To prove (M+1) (m-1 )is an rational number |
| Answer» But how | |
| 28552. |
What is drift speed? |
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Answer» The velocity gained by the accelerating electrons in uniform electric field inside the conductor is drift velocity. The average velocity, acquired by free electrons along the length of a metallic conductor, due to existing electric field is called drift velocity.\xa0Let ‘n’ be the number density of free electrons in a conductor of length ‘l’ and area of cross-section ‘A’.\xa0Total charge in the conductor, Q = Ne = (nAl)eTime taken, t is given by,\xa0Therefore, the current flowing across the conductor is given by,\xa0That is,\xa0, which is the amount of current flowing through a conductor in terms of drift velocity. Chapter electricity Sorry bro/sis it is of science |
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| 28553. |
Show that the square of any positive interger cannot be of the form 5q+2 or 5q+3 for any integer q. |
| Answer» Let n be any positive integer. Applying Euclids division lemma with divisor = 5, we get{tex}\\style{font-family:Arial}{\\begin{array}{l}n=5q+1,5q+2,5q+3\\;and\\;5q+4\\;\\\\\\end{array}}{/tex}Now (5q)2 = 25q2 = 5m, where m = 5q2, which is an integer;{tex}\\style{font-family:Arial}{\\begin{array}{l}(5q\\;+\\;1)^{\\;2}\\;=\\;25q^2\\;+\\;10q\\;+\\;1\\;=\\;5(5q^2\\;+\\;2q)\\;+\\;1\\;=\\;5m\\;+\\;1\\\\where\\;m\\;=\\;5q^2\\;+\\;2q,\\;which\\;is\\;an\\;integer;\\\\\\;(5q\\;+\\;2)^2\\;=\\;25q^2\\;+\\;20q\\;+\\;4\\;=\\;5(5q^2\\;+\\;4q)\\;+\\;4\\;=\\;5m\\;+\\;4,\\\\\\;where\\;m\\;=\\;5q^2\\;+\\;4q,\\;which\\;is\\;an\\;integer;\\\\\\;(5q\\;+\\;3)^{\\;2}\\;=\\;25q^2\\;+\\;30q\\;+\\;9\\;=\\;5(5q^2\\;+\\;6q+\\;1)\\;+\\;4\\;=\\;5m\\;+\\;4,\\\\\\;where\\;m\\;=\\;5q^2\\;+\\;6q\\;+\\;1,\\;which\\;is\\;an\\;integer;\\\\\\;(5q\\;+\\;4)^2\\;=\\;25q^2\\;+\\;40q\\;+\\;16\\;=\\;5(5q^2\\;+\\;8q\\;+\\;3)\\;+\\;1\\;=\\;5m\\;+\\;1,\\;\\\\where\\;m\\;=\\;5q^2\\;+\\;8q\\;+\\;3,\\;which\\;is\\;an\\;integer\\\\\\end{array}}{/tex}Thus, the square of any positive integer is of the form 5m, 5m + 1 or 5m + 4 for some integer m.It follows that the square of any positive integer cannot be of the form 5m + 2 or 5m + 3 for some integer m. | |
| 28554. |
Factorise x3-3x+2 |
| Answer» | |
| 28555. |
D is a point on side BC of triangleABC such that BD/CD=AB/AC .prove that AD is the bisector of |
| Answer» In the figure, D is a point on side BC of {tex}\\triangle {/tex} ABC such that.{tex}\\frac{{BD}}{{CD}} = \\frac{{AB}}{{AC}}{/tex}To prove, AD is the bisector of{tex}\\angle{/tex} BACConstruction: From BA produce cut off AE = A. Join CEProof:{tex}\\frac{{BD}}{{CD}} = \\frac{{AB}}{{AC}}{/tex} ........Given{tex}\\Rightarrow {/tex}{tex}\\frac{{BD}}{{CD}} = \\frac{{AB}}{{AE}}{/tex}\xa0{tex}\\because {/tex} AC = AE(by construction){tex}\\therefore {/tex} In \u200b{tex}\\triangle {/tex}\u200b BCE,AD\xa0{tex}\\parallel{/tex} CE ............By converse of the basic proportional theorem{tex}\\therefore {/tex}{tex}\\angle{/tex}BAD = {tex}\\angle{/tex}AEC .......(1)...........Corres. {tex}\\angle{/tex} s{tex}\\angle{/tex}CAD = {tex}\\angle{/tex}AEC ..........(2) ........Alt,Int. {tex}\\angle{/tex} s{tex}\\therefore {/tex} AC = AE .........By construction{tex}\\therefore {/tex}{tex}\\angle{/tex}AEC = {tex}\\angle{/tex}ACE ............(3)...angles opposite equal sides of a triangle are equalUsing (3),(1) and (2) gives {tex}\\angle{/tex}BAD = {tex}\\angle{/tex}CAD | |
| 28556. |
Military mein jaane ke liye konsa subect lena hoga 11th mein ?? |
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Answer» You can take humanities it will help u Aap sbhi ne news dekha 14th feb ka Join army school |
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| 28557. |
If x=2/3 and x=-3 are the zeros ofax^2+ bx+ c= 0 find a and b |
| Answer» If nth term of an AP is 2n+1Then, first term of an AP =2(1)+1... =2+1. .. =3Then, Second term = 2(2)+1=5Third term = 2(3)+1=7Sun of three term= 3+5+7=15Answer is _15_ | |
| 28558. |
Find the value of k if the quadratic equation 3 x square - ke root 3 X + 4 0 has no equal |
| Answer» K=+-4 | |
| 28559. |
If nth term of an A.P is (2n+1) what is the sum of first three terms |
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Answer» nth term = 2n+11st term = 32nd term = 53rd term = 7Sum = 3+5+7= 15 You can solve this asan = 2n + 1Now a1 = 2 (1) + 1 =3a1 = 3 ,Similarly a2 = 2(2) + 1 = 5 a3 = 7 Now sum of first three terms Put the formula And this would be ur answer = 15 I think this is the perfect answer Hope u understand? 15 |
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| 28560. |
7 ×11 × 13 + 7 is a composite number or a prime number |
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Answer» Composit number because composit x composit = composit . Also primr x composit = composit 7×11×13+7=7(1×11×13+1) 7(243+1)7×2447×2×2×61It has more than two factor so it is a composite number 7×11×13+7=7(11×13+1)=7×144Therefore the given number is product of 7 and 144 . So it\'s a composite number. |
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| 28561. |
what is the digit at unit place of 9n |
| Answer» 9n = (3×3)n . 3 can never ends with zero. So, 3 is the digit at unit place of 9n.??. I am not sure about my answer | |
| 28562. |
How image is sent..!??? |
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Answer» How???? thsi question you ask mycbseguide at 092135 22769 |
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| 28563. |
Determine the ratio of line segment 2x+y-4= 0 divides the line segment joining points (2;-2)(3;7) |
| Answer» X=3alpha+2÷alpha+1Y=7alpha-2÷alpha+1Now,2x+(y-4)=0Putting the value of x&y in this equation.2×(3alpha+2÷alpha+1)+(7alpha -2÷alpha+1)-4=06alpha+4+7alpha-2÷alpha+1=413alpha+2÷alpha+1=413alpha+2=4alpha+413alpha-4alpha=4-29alpha=2alpha=2/9Therefore, the ratio is 2:9 | |
| 28564. |
How to convert 240m/s into km/h |
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Answer» {tex}\\begin{array}{l}\\text{240 m/s=}\\frac{\\displaystyle240/1000\\;(\\mathrm m\\;\\mathrm{to}\\;\\mathrm{km})}{1/3600\\;(\\mathrm s\\;\\mathrm{to}\\;\\mathrm{hr})}\\\\=\\frac{\\displaystyle240}{1000}\\times\\frac{3600}1\\\\=24\\times36=860\\;\\mathrm{km}/\\mathrm{hr}\\end{array}{/tex}\xa0 240×60×60÷1000 km per hour Multiply by 18/5 |
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| 28565. |
if the cube a of 3 digit no. is 1331 and has sum of its digit equal to 3 find the no.? |
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Answer» Cube root of 1331 is 11 and sum of digits is 2 pl write question correctly sorry 2 digit no. h ok |
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| 28566. |
probability of an event is.....???..... |
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Answer» P(E)=No.of outcomes favourable to E /Total no. Of outcomes. 1 Event* Sure eveng is 1 and impossible event is 0 |
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| 28567. |
How many centroid in triangle |
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Answer» The centroid is the intersection of the three medians. The three medians also divide the triangle into six triangles, each of which have the same area.so triangle is having only one centroid 1 3 |
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| 28568. |
Find HCF (865,255) using euclid division lemma |
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Answer» Let a=865. b=255By Euclid division lemma865=255×3+100255=100×2+55100=55×1+4555=45×1+1045=10×4+510=5×2+0HCF=5 5 |
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| 28569. |
a circle ha .......... parallel tangenta? |
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Answer» 2 2 2 |
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| 28570. |
Find the sum of all multiples of 7 lying between 500 and 900 |
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Answer» 39900 sum 504 , 511 , 518 , ....,889, 896 are multiples of 7 between 500 and 900 and these are in Arithmetic progression .First term = a = 504 , Common difference = a2 - a1 = d = 511 - 504 = 7Let the number of terms = nLast term ( L ) = 896We know that ,a + ( n - 1 )d = L504 + ( n - 1 ) 7 = 896Divide each term with 7 , we get72 + n - 1 = 12871 + n = 128n = 128 - 71n = 57\xa0 Calculate? |
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| 28571. |
What is the value of X if the median of the following data is 27.5 ? 24 25 26 x+2 x+3 30 33 37. |
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Answer» If we will take class interval of h=10 then x=77.5 Laa,where is the class interval? Calculate? |
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| 28572. |
a²(b+c)+b²(c+a)+c²(a+b)-2b²c |
| Answer» a2(b+ c) + b2(c + a) + c2 (a+ b) - 2b2c= a2b + a2c + b2c + b2a + c2a + c2b - 2b2c= a2b + a2c + b2c - 2b2c + b2a + c2a + c2b= a2b + a2c - b2c + b2a + c2a + c2b\xa0 | |
| 28573. |
Cosα\\cosβ=m and cosα\\sinβ=n then prove (m^2+n^2)cos^2β=n^2 |
| Answer» Put the value of m^2 & n^2 | |
| 28574. |
If the numbers a,b,c,d,e form an A.P., then find the value of a-4b+6c-4d+e |
| Answer» | |
| 28575. |
(a-b) x²+(b-c) x+(c-a), it\'s roots are equal, then prove that 2a=b+c |
| Answer» We know that,If the quadratic equation ax²+bx+c=0whose roots are equal then it\'s deteminant is equal to zero.(a-b)x²+(b-c)x+(c-a)=0Deteminant =0(b-c)² -4(a-b)(c-a)==0b²+c²-2bc-4ac+4a²+4bc-4ab=0b²+c²+4a²+4bc-4ac-4ab=0b²+c²+(-2a)²+2bc+2c(-2a)+2(-2a)b=0(b+c-2a)²=0b+c-2a=0Therefore,b+c=2aHence proved.I hope this helps you. | |
| 28576. |
Solve for x (in term of a and b) a/x-b +b/x-a=2 |
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Answer» a/x-b +b/x-a=2a-bx+b-ax=2x-ax-bx-2x= -a -b-(a+b+2)x = -(a+b)x=(a+b) /(a+b+2)- X=3/2(a+b) |
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| 28577. |
In figure if AD = 6cm, DB = 9cm, AE = 8cm and EC = 12cm and angle ADE is 48 degree.find angle ABC |
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Answer» Figure????? If the figure ain\'t shown then we cannot answer! Where is the figure? |
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| 28578. |
Anyone knows French |
| Answer» heean | |
| 28579. |
What is a homologous serious of carbon compound |
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Answer» It is a series of compound in which some functional group subsitutes for hydrogen in a carbon chain e.g.-ch3cooh, C2H5OH The series which differ for ch2 of any functinal group Same in structure |
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| 28580. |
Ram ram friends |
| Answer» ???? | |
| 28581. |
Also me too |
| Answer» | |
| 28582. |
What is the value of √[sin^2(30)*cos ^2(60)] |
| Answer» √sin²30°×cos²60° Sol. Sin30°=1/2 therfor sin²30=(1/2)² Cos60°=1/2 similar cos²60=(1/2)² √sin²30×cos²60 √(1/2)²×(1/2)² √1/4×1/4 √1/16 1/4 answer | |
| 28583. |
Plz tell the statement of alternative segment theorm |
| Answer» | |
| 28584. |
A trader with a basket of egg |
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Answer» ????.... Pls complete your question... Complete yur ques... |
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| 28585. |
Find the area. Of quadrant of circle whose circumference is 22 |
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Answer» 77/8 38.5 |
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| 28586. |
The nth term of an AP is 6n + 2, find its common difference |
| Answer» 6 | |
| 28587. |
1+sinA-cosA/1+sinA+cosA=√1-cosA/√1+cosA. Prove |
| Answer» | |
| 28588. |
10x^2+24x-4 split the term |
| Answer» This could not be split. So you have to use method of quadratic equation | |
| 28589. |
K के किस मान के लिए 2K, K+10 और 3K+2 समांतर श्रेणी में है ? |
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Answer» Bcoz t2-t1=t3-t2 K+10-2K=3K+2-K-10 6 |
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| 28590. |
Cos A minus Sin A + 1 by Cos A + Sin A minus 1 is equal to Cosec A + cot A proof it |
| Answer» LHS side leke use sinA se divide kero sehi solve keroge to answer aayega seb ko divide ker dena puri LHS side ok | |
| 28591. |
Calculate the area bounded by the line x+y=10 and both the coordinate axis ?? |
| Answer» 50 | |
| 28592. |
Sample paper 3rd |
| Answer» Check sample papers here :\xa0https://mycbseguide.com/cbse-sample-papers.html | |
| 28593. |
Find the distance between the two point p(3,4) and the origin |
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Answer» Explanation.. formulae of dis.of any point from origion is √x^2+y^2... 5 units Its 5.. 5 unitsssss |
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| 28594. |
Aera related circle all are the formule |
| Answer» Check out in yur book.......? | |
| 28595. |
2n-1 |
| Answer» Let n=1,2,3_ _ _ _So, put these in 2n-1 Thus, AP=1,3,5_ _ _ Where a=1and d=2 | |
| 28596. |
if -2x. X+10. 3x+2 are in so find the car e of x |
| Answer» lf 2x, x + 10, 3x + 2 are in A.P.,we have to find the value of x.Since, 2x, x + 10, 3x + 2 are in A.P.therefore 2 (x + 10) = 2x + 3x + 2{tex}\\Rightarrow{/tex}\xa02x + 20 = 5x + 2{tex}\\Rightarrow{/tex}\xa03x = 18 {tex}\\Rightarrow{/tex}\xa0x = 6\xa0\u200b\u200b | |
| 28597. |
Check whether -150 is a term of the ap: 11,8,5,2.... |
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Answer» A=11 D=-3LET Tn=-150-150 = 11+(n-1)(-3)-150=11-3n+3-3n=-164n=164/3=54.66n is not a integer so -150 is not term of AP An=-150......a=11.....d=-3........an=a+(n-1)d......-150=11+(n-1)-3......-139/-3=n-1.....answer will be in decimal so it is not a term of a.p |
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| 28598. |
If in an equilateral triangle,the length of a median is √3cm ,then find the length of the side |
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Answer» Let the length of side be xApplying Pythagoras theorem,\xa0(√3)²+(x/2)²=x²3+(x²/4)=x²(12+x²) /4=x²12+x²=4x²12=4x²-x²12=3x²4=x²√4=x2=xThen length of side is 2cm 2 cm 2cm |
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| 28599. |
Sin2x=2sinxcosx |
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Answer» We know,\xa0one important identity ,\xa0sin( A + B) =sinA.cosB + cosA. sinB\xa0let A = x\xa0B = x\xa0then,\xa0sin( x + x ) = sinx.cosx + cosx .sinx\xa0sin2x = 2sinx.cosx\xa0verify :-\xa0Let x = 30°\xa0LHS = sin60° = √3/2\xa0RHS = 2sin30°.cos30° = 2× 1/2 × √3/2 =√3/2\xa0LHS = RHS\xa0this is true for all real value of x then ,sin2x = 2sinx.cosx is also an identity. We knowsin(x+y)=sinxcosy+cosxsinyif x=y thensin(x+x)=sinxcosx+cosxsinxsin2x=2sinxcosx |
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| 28600. |
for what value of n 2power n into 5 power n ends with 5 |
| Answer» {tex}\\begin{array}{l}2^n\\times5^n=10^n\\\\If\\;n=0\\;then\\;10^n=1\\\\If\\;n>0\\;then\\;10^n\\;ends\\;with\\;0\\\\If\\;n<0\\;then\\;10^n\\;1s\\;in\\;form\\;0.1,\\;0.01--\\\\\\end{array}{/tex}Hence for any value of n 2^n x 5^n can not end with 5 | |