Question

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

17. (1,4),(2,12)

Answer 1

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