q = -1 ; q= 3
There are two ways, either you can use Log or exponent rule (a^m)^n = a^(m × n):
I'll be using the exponent rule.
4^(q²-3) - 16^q = 0
It can also be written as:
4^(q²-3) - (4^2)^q = 0
Thus: 4^(q²-3) - 4^2q = 0
4^(q²-3) = 4^2q
since the base is same, comparing the exponents
(q²-3) = 2q
q² - 2q - 3 = 0
Using mid term factorisation
q² - 3q + q - 3 = 0
q (1q - 3) + 1 (q - 3) = 0
(q-1) (q-3) = 0
Thus, q = - 1
q= 3