[填空题]
A toy racing car is drivie lht2pm xr 1;2ui4 86b+exptfng ovut ejauu ,w;,n.u0*uwer a hill on a path that can be modelled by part of the function
w0uuun w;, .a,j*uut e f(x)=-$\frac{1}{4}x^2+5$.
1.Find the gradient of the hill at the point where x=2.
f'(2)=- .
2.Find the x value of the point where the gradient perpendicular to the hill is equal to $\frac{3}{2}$.
the number is $\frac{a}{b}$ ,a= , b= .
