Question

Graph the function f(x) = 5(0.21)x.

an exponential graph decreasing from the left and crossing the y axis at 0 comma 21
an exponential graph decreasing from the left and crossing the y axis at 0 comma 5
an exponential graph decreasing from the left and crossing the y axis at 0 comma 18
an exponential graph decreasing from the left and crossing the y axis at 0 comma 8

Answer 1

The answer is b

Answer 2

This is an exponential graph decreasing from the left and crossing the y-axis at 0 comma 5.

Explanation:

The given function is
`f(x) = 5(0.21)^(x)`

Since, the base of the function is 0.21 which is a fraction, so as the value of exponent x increases the value of function f(x) decreases.

Now, the y-intercept of the function is at x = 0 ans hence,
`f(x) = y = 5(0.21)^(0) = 5` {Since,
`a^(0) = 1` for all a ≠ 0}

Therefore, the graph of the function crosses y-axis at (0,5) point.

So, this is an exponential graph decreasing from the left and crossing the y-axis at 0 comma 5. (Answer)