This online calculator will solve for X in A^X = B. A raised to the X power equals B. Enter A and B and this calculator will solve for the exponent X. Note that -43 = -1 * 4 * 4 * 4 = -1 * 64 = -64. See notes for exponents.
For A^X = B we can solve for X by taking the log of both sides so:
log(A^X) = log(B)
X * log(A) = log(B)
Dividing both sides by log(A) we get:
X = log(B) / log(A).
Since taking the log() of negative numbers, 0 or 1 causes calculation errors we have provided some answers by definition and not actual calculations.