plisss bantuin dong no.15

jawab

ᵃlog b + ᵇlog a⁴ + 4 = 0
ᵃlog b + 4 (ᵇlog a) + 4 = 0

misalkan 
ᵃlog b = x → ᵇlog a = 1/x

x + 4 (1/x) + 4 = 0 ....}kalikan x
x² + 4 + 4x = 0
x² + 4x + 4 = 0
(x + 2)² = 0
x  = - 2

ᵃlog b = - 2 → a⁻²  = b → a² = (1/b)

nilai dari
a² b - ᵃlog b =  (1/b)(b) - (-2)
= 1 + 2
= 3