G(x)=x^2+4 (GoF)(x)=9x^2+12x F(x)=-1 ?

langsung aja y

(gof)(x) = g{f(x)}

9x² + 12x = f(x)² + 4

9x² + 12x - 4 = f(x)²

√9x² + 12x - 4 = f(x)

f(-1) = √9(-1)² + 12(-1) - 4

f(-1) = √ 9 - 12 - 4

f(-1) = √-7

semoga berguna +_+