Q. Write an exponential function in the form y=abx that goes through the points (0,15) and (4,1215).Answer:
Find a Value of a: We need to find the values of a and b for the exponential function y=ab(x) that passes through the points (0,15) and (4,1215). Let's start by using the point (0,15).Substitute x=0 and y=15 into the equation y=ab(x) to find the value of a.b0b1Since any number to the power of b2 is b3, we have:b4Therefore, b5.
Find a Value of b: Now let's use the point (4,1215) to find the value of b.Substitute x=4, y=1215, and a=15 into the equation y=abx to find the value of b.1215=15b4To solve for b, divide both sides by 15:151215=b481=b4To find b, we take the fourth root of both sides:b=8141b=3
Write Exponential Function: Now that we have both a and b, we can write the exponential function.a=15 and b=3, so the function is:y=15×3xThis is the exponential function that goes through the points (0,15) and (4,1215).
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