If the line $y=mx+1$ is tangent to the parabola $y^2=4x$ then find the value of $m$.

Question

[Hint:Solving the equation of line and parabola,we obtain a quadratic equation and then apply the tangency condition giving the value of $m$].

$\begin{array}{1 1}2\\-2\\\large\frac{1}{2}\\-\large\frac{1}{2}\end{array}$