Question

Write an exponential function of the form y=ab^x whose graph passes through the given points.

Answer 1

$We\ substitude\ points\ into \ formula:\\ y= ab^{x}\\\{ {{4=ab^1} \atop {12=ab^2}} \right. |Substitude\ a= \frac{4}{b} \ from\ first \ equation\\12= \frac{4}{b}*b^2\\ 12=4b|:4\\ b=3\\a= \frac{4}{3} \\ y=4^x$