Hi, could someone please help me with part (a) of this question. I understand everything except that part...
Thanks heaps.
Note that $\displaystyle L$ is the tangent line to $\displaystyle y^2=4x$ at $\displaystyle (x_0,y_0)$.
$\displaystyle \beta$ is the angle $\displaystyle L$ makes with the positive $\displaystyle x$-axis. So the slope of $\displaystyle L$ is $\displaystyle \tan(\beta)$.
But that slope is $\displaystyle \\2yy'=4p\\y'=\frac{2p}{y}~.$