COMEDK2021MathematicsApplication of Derivatives
The equation of normal to the curve y=(1+x)^ y + ⁻¹ ( ² x ) at x=0 is
Options
- Ax+y=1
- Bx-y=1
- Cx+y=-1
- Dx-y=-1
Correct answer
A. x+y=1
Step-by-step solution
Given the curve y = (1+x)^ y + ⁻¹( ²x) . At x = 0 , y = (1+0)^ y + ⁻¹( ²0) = 1^ y + 0 = 1 . Thus, the point of contact is (0, 1) . To find the slope of the tangent, differentiate the equation with respect to x : Let u = (1+x)^ y . Then u = y (1+x) . Differentiating with respect to x : 1 u du dx = dy dx (1+x) + y 1+x . So, du dx = (1+x)^ y [ dy dx (1+x) + y 1+x ] . At (0, 1) , du dx = 1¹ [ dy dx (1) + 1 1 ] = 1 . Now differentiate ⁻¹( ²x) with respect to x : d dx [ ⁻¹( ²x)] = 1 1 - ( ²x)² 2 x x = 2x 1 - ⁴x . At x =