1. The function f(x) = (x2 – 1) |x2 – 3x + 2| + cos (|x|) is not differentiable at :(A) x = –1 (B) x = 0(C) x = 1 (D) x = 22. y = 2-logz(x3-5) , then dy/dx is(A)-3x2/(x3-5)2(B) x2/(x3-5)2(C)3x2/(x3-5)2(D) none of these3. y = esin 2x, then dy/dx is(A) x cos 2x(B) 2y cos 2x(C) xy cos 2x(D) none of these4. y = (sinx + cosx)x , then dy/dx is(A) y(sinx + cosx)(B) y{log y/x + x(cosx - sinx)/(sin x+cos x)}(C) y(log y/x + y2 )(D) none of these5. y = eloge(sin-1x + cos-1x), then dy/dx is(A) 5(B) 2(C) 0 (D) none of these

Dear kanika,

1)The function is not differentiable at the critical points or sudden turn is there in the curve..

c) is the correct choice.

2)the correct answer is a) becoz the differentiation of 1/x is -1/x^2.use this property

and log_aa=1 and a^log_ax =x

3)The correct choice is b)

4) The correct choice is b)

5)c)

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