The equation of the normal to the curve `x=a\ cos^3theta,\ \ y=a\ s in^3theta` at the point `theta=pi//4` is `x=0` (b) `y=0` (c) `x=y` (d) `x+y=a`

Explanation

Slope of normal to the curve 'm'= =`-1/(dy/dx​)_(θ=π/4)​`
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`x=acos^3θ,y=asin^3θ`


`dx/dt heta​=3acos^2θ(−sinθ)`

`dy/d theta​=3asin^2θcosθ`

so,`dy/dx=−tanθ`

at `theta=pi/4`

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