1.

if `y=(sin(x+9))/(cosx)`, then `(dy)/(dx)` at x=0 is equal toA. cos9B. sin9C. 0D. 1

Answer» Correct Answer - a
Given, `y=(sin(x+9))/(cosx)`
`therefore (dy)/(dx) = (cosxcos(x+9)-sin(x+9)(-sinx))/(cosx)^(2)` [by quotient rule]
`=cosxcos(x+9)+sinxsin(x+9)/(cos^(2)x)`
`therefore ((dy)/(dx))_(x=0) = (costheta)/(1) = costheta`


Discussion

No Comment Found