An exponential function is graphed in the xy-plane. If the graph of the function is always increasing and its y-intercept is (0,6), which of the following could be the equation of the function?Choose 1 answer:(A) y=6(0.5)x(B) y=12(0.5)x(C) y=6(2)x+1(D) y=4(2)x+2
Q. An exponential function is graphed in the xy-plane. If the graph of the function is always increasing and its y-intercept is (0,6), which of the following could be the equation of the function?Choose 1 answer:(A) y=6(0.5)x(B) y=12(0.5)x(C) y=6(2)x+1(D) y=4(2)x+2
Exponential Function Behavior: An exponential function of the form y=abx is always increasing if the base b is greater than 1. This is because as x increases, the value of bx increases when b > 1.
Finding Y-Intercept: The y-intercept of a function is the value of y when x=0. For an exponential function y=abx, the y-intercept is found by setting x to 0, which gives y=ab0=a. Therefore, the y-intercept is (0,a).
Determining Correct Function: Given that the y-intercept is (0,6), we can determine that a must be 6 for the correct function. We can now check the options to see which one has a y-intercept of 6 and a base greater than 1.
Option (A) Analysis: Option (A) y=6(0.5)x has a base of 0.5, which is less than 1. This means the function is decreasing, not increasing. Therefore, option (A) is not the correct function.
Option (B) Analysis: Option (B) y=12(0.5)x has a base of 0.5, which is less than 1. This means the function is decreasing, not increasing. Additionally, the y-intercept is 12, not 6. Therefore, option (B) is not the correct function.
Option (C) Analysis: Option (C) y=6(2)x+1 has a base of 2, which is greater than 1, indicating an increasing function. However, when x=0, y=6(2)0+1=6(1)+1=7, not 6. Therefore, option (C) does not have the correct y-intercept.
Option (D) Analysis: Option (D) y=4(2)x+2 has a base of 2, which is greater than 1, indicating an increasing function. However, when x=0, y=4(2)0+2=4(1)+2=6. This function has the correct y-intercept of 6. Therefore, option (D) is the correct function.
More problems from Compare linear and exponential growth