1)

The equation of normal to the curve y=(1+x)y+sin1(sin2x) at x=0 is 


A) x+y=1

B) x-y=1

C) x+y=-1

D) x-y=-1

Answer:

Option A

Explanation:

Given curve is 

  y(1+x)y+sin1(sin2x)

 On  differentiating w.r.t x , we get

  dydx=(1+x)y[y1+x+log(1+x)dydx]+2sinxcosx1sin4x

     (dydx)at(0,1)=1[atx=0,y=1]

 Slope of normal at (x=0)=-1

  Equation of normal at x=0 and y=1 is  y-1=-1(x-0)

    y1=xx+y=1