Under what condition is the tangent to a given curve at a given curve at a point perpendicular to x axis?

Options

A. `(dy)/(dx)=0`
B. `(dy)/(dx)=1`
C. `(dx)/(dy)=0`
D. `(d^(2)y)/(dx^(2))=1`

Answer

C

Explanation

Tangent to given curve at a point is perpendicualr to x axis gives `(dy)/(dx) = tan(pi)/(2)`
`rarr (dx)/(dy)= cot(pi)/(2)=0`