KCET2013MathematicsApplication of Derivatives
If the length of the subtangent at any point to the curve x y^ n =a is proportional to the abscissa, then n is
Options
- Aany non-zero real number
- B2
- C-2
- D1
Correct answer
A. any non-zero real number
Step-by-step solution
Given, curve is x y^ n =a On differentiating w.r.t. x , we get x n y^ n-1 d y d x +y^ n =0 y^ n-1 [x n d y d x +y ]=0 d y d x =- y n x ( y 0) aligned Length of subtangent &= y (d y / d x) &=y ( -n x y )=-n x aligned Since, it is proportional to x . So, n can be any non-zero real number.