00:01
Let's determine the zeros of this function, f of x equals minus 9 times of x minus 7 times of x plus 7 raised to the power of 3.
00:09
So to determine the zeros, we have to replace f of x equals 0 and solve for x.
00:16
So we put f of x equals 0.
00:21
I'm going to replace f of x equals 0 in this function.
00:25
So we get 0 equals negative 9 times of x minus 6.
00:32
Times of x plus 7 raised to the power of 3 we can divide by negative 9 on both sides so 0 by negative 9 and this equals negative 9 over negative 9 we get x minus 6 times of x plus 7 raised to the power of 3 so 0 by negative 9 is once again 0 and negative 9 by negative 9 this equals 1 so it's basically 1 times of this expression which is x minus 6 times of x plus 7 quantity cube.
01:09
Now one of them is 0, that is either x minus 6 is 0 or we will have x plus 7 quantity cube.
01:22
This equals 0 because this is a product of two linear terms.
01:27
So either one can be 0.
01:28
When we solve this expression x minus 6 equals 0, we get x equal to 6.
01:34
And similarly, we can solve this expression or the equation x plus 7 quantity cube equal to 0 by taking cube root on both sides.
01:43
So when we do that, we get x plus 7 equals 0 because cube root of 0 is 0.
01:49
Now we solve for x, that is x equal to negative 7.
01:53
And since we are taking a cube root to solve this x, we will have a multiplicity of 3 for this negative 7.
02:02
So we say that this is with multiplicity 3.
02:06
So these are the zeros of this function.
02:10
So we say that the zeros of this function are 6 and minus 7.
02:16
And this minus 7 is with multiplicity 3.
02:24
Let's choose the correct choice given below...