the function f is such that f(x)=(2x-7)/4. Fnd f(-7) and the inverse of the function.
to find the first part we just need to plug in the value-7 in the expression for f replacing our independant value, x .f(-7)=(2*(-7)-7)/4 =(-14-7)/4 =-21/4to find the second part we need to interchange the position of x and y.here we set y as f(x). y=(2x-7)/4interchange their position: x=(2y-7)/4and then rearrange to make the new y the subject again. 4x=2y-74x+7=2y2x+7/2=yhence the invesrse function : f^-1(x)= 2x+7/2
EG
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