To find the expressions that replaces the x in f(x), we have to replace the x in the equation with whatever is in the bracket, so if
f(x) = (x^2-4)/(x-1)f(x)=x2−4x−1
f(0) = (0^2-4)/(0-1)= (-4)/(-1)=4f(0)=02−40−1=−4−1=4
f(1/2) = ((1/2)^2-4)/((1/2)-1)=((1/4)-4)/((1/2)-1)=15/2f(12)=(12)2−4(12)−1=(14)−4(12)−1=152
f(-2) = ((-2)^2-4)/((-2)-1)=(0)/-3=0f(−2)=(−2)2−4(−2)−1=0−3=0
f(x-2) = ((x-2)^2-4)/((x-2)-1)=(x^2-4x+4-4)/(x-3)=(x(x-4))/(x-3)f(x−2)=(x−2)2−4(x−2)−1=x2−4x+4−4x−3=x(x−4)x−3
f(r^2) = ((r^2)^2-4)/((r^2)-1)=(r^4-4)/(r^2-1)f(r2)=(r2)2−4(r2)−1=r4−4r2−1
f(1/t) = ((1/t)^2-4)/((1/t)-1)=((1/t^2)-4)/((1/t)-1)f(1t)=(1t)2−4(1t)−1=(1t2)−4(1t)−1
