1.

`lim_(x-> pi/4) (4sqrt2-(cosx+sinx)^5)/(1-sin2x)`A. `5sqrt(2)`B. `3sqrt(2)`C. `sqrt(2)`D. none of these

Answer» Correct Answer - A
`lim_(xto pi//4)(4sqrt(2)-(cosx+sinx)^5)/(1-sin2x)`
`=lim_(x+pi//4)({(cos x +sin x)^2}^(5//2)-(2)^(5//2))/((1+sin2x)-2)`
`=lim_(x to pi//4)((1+sin2x)^(5//2)-2^(5//2))/((1+sin2x)-2)`
`=lim_(y+2)(y^(5//2)-2^(5//2))/(y-2),"where " y=1 +sin 2x`
`=(5)/(2)xx2^(5//2-1)=5sqrt(2)`


Discussion

No Comment Found