If a and b are nonzero real numbers and (3.92)a = (7.86)b, what is the value of (b/a)^2? The answer is .44. The answer says use logs, so I took the log of both sides. Then they say to use the power rule. I thought the a and b would have to be an exponent to use the power rule? Do they, or is the answer explanation I'm reading correct?