Practicing Success
The slope of the normal to the curve $y=2 x^2-4$ at $P(1,-2)$ is : |
4 -4 $-\frac{1}{4}$ 0 |
$-\frac{1}{4}$ |
$y=2 x^2-4$ at $(P(1,-2))$ slope of tangent at $P=\frac{d y}{d x}=\frac{d}{d x}\left(2 x^2-4\right)$ $\Rightarrow \frac{d y}{d x} =4 x$ so $\left.\frac{d y}{d x}\right]_{(1,-2)}=4(1)=4$ So we know that at any point slope of tangent (m) × slope of normal (n) = -1 so $4 \times n=-1$ $n=-\frac{1}{4}$ (slope of normal at P) |