Answer Choices
f(x) = (x-3)
f(x) = (x-3)(x-1)^2
f(x) = (x-1)(x+1)(x+3)
f(x) = (x+1)^2(x+3)
Explanation for Question 12 From the Math (Calc) Section on the Official Sat Practice Test 4
Now here in number 12, we're looking at the X, Y plane of a 2 function that has intercepts that negative three negative one and one. 3 Right. And our question is which of the following could define F and so 4 the important thing to know here is that X intercepts are also, 5 um, zeros, right? 6 So when you solve for the zeros of the function, you're really finding the 7 X intercepts. Now, if I have X intercepts that negative three negative one and 8 one, right? So in other words, X is equal to negative. 9 Three X is equal to negative one and X is equal to one. 10 Then I need to take these three equations and write them more as 11 expressions, right? Without an equal sign, 12 so that I have X with something. So if I add three to both 13 sides, so that I have everything on the same side of the equal side, 14 I get X plus three is equal to zero, 15 right? 16 So I need an answer choice that has an X plus three in it. 17 And the only ones that we see that in here are either C or 18 D. And so now we can look at, 19 uh, X equals negative one and X equals positive one, 20 right? So I'll add one to both sides. So I get X plus one 21 subtract one from both sides here, and I need an X minus one. 22 And we see that only in C, M, 23 D actually leaves out the X minus one. 24 So that means that C must be our answer. And so just to kind 25 of summarize, um, basically whatever numbers you actually have as your zeros, 26 you kind of want the opposite side within your parentheses. 27 So if you have a negative three zero, you want X plus three in 28 your parentheses of your function. And that leads us against the answer choices. 29 See.