g(f(x))=4(45)2−10.45+5=−45
g(f(45))=f2(45)+f(45)−1
−45=f2(45)+f(45)−1
f2(45)+f(45)+41=0
(f(45)+21)2=0
f(45)=−21
If g(x)=x2+x−1 and (gof)(x)=4x2−10x+5, then f(45) is equal to
Held on 7 Jan 2020 · Verified 6 Jul 2026.
23
−21
21
−23
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