ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos


ACT Math Videos 161 videos

ACT Math 3.1 Plane Geometry
2559 Views

ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?

ACT Math 2.2 Pre-Algebra
421 Views

ACT Math Pre-Algebra: Drill 2, Problem 2. Solve for y.

ACT Math 2.5 Pre-Algebra
425 Views

ACT Math Pre-Algebra Drill 2, Problem 5. Given the chart in the video, what is the mode?

See All

ACT Math 6.1 Elementary Algebra 214 Views


Share It!


Description:

ACT Math: Elementary Algebra Drill 6, Problem 1. Which of the following is not a factor of x 3 – x?

Language:
English Language

Transcript

00:02

And here's another shmoop du jour... Which of the following is not a factor of

00:06

x cubed minus x?

00:08

And here are the potential answers...

00:14

Okay can we factor?

00:15

Here, the common element on both sides of the minus sign is x.

00:19

If we pull out that x...

00:20

...we get x times the quantity x squared minus 1.

00:24

But now we have x squared minus 1... it's a magic number we should recognize.

00:29

X squared minus 1 is a factorable beast...

00:33

...in quantity x plus 1 times quantity x minus 1.

00:38

So the factors are x... then quantity x plus 1... then quantity x minus 1.

00:43

If we look down our answers list, the only factor left that ISN'T an element of this

00:47

equation is x squared plus 1...

00:49

... so the answer is... E.

Related Videos

ACT Math 3.1 Plane Geometry
2559 Views

ACT Math: Plane Geometry Drill 3, Problem 1. What is the area of the trapezoid shape in the video?

Inequalities in Number Lines
3229 Views

ACT Math: Coordinate Geometry Drill 1, Problem 1. Which inequality is expressed by the number line?

ACT Math 3.1 Intermediate Algebra
1955 Views

ACT Math: Intermediate Algebra: Drill 3, Problem 1. Find the fifth number in the series.

CAHSEE Math 6.2 Algebra I
290 Views

CAHSEE Math: Algebra I Drill 6, Problem 2. Simplify the polynomial.