ShmoopTube

Where Monty Python meets your 10th grade teacher.

Search Thousands of Shmoop Videos

CAHSEE Math 4.2 Number Sense 205 Views


Share It!


Description:

Number Sense: Drill Set 4, Problem 2. Simplify the expression.

Language:
English Language

Transcript

00:03

And here's your shmoop du jour.

00:06

Simplify the expression (4a to the -2) quantity to the -1.

00:12

And here are the possible answers...

00:18

Ok, this question is testing whether we have learned to love the negative exponent.

00:22

And yeah, negative exponents just mean "one over", more or less.

00:28

Remember order of operations, or PEMDAS?

00:31

This tells us that we have to start with the parentheses to simplify this expression.

00:37

So let's start in the middle of the cave and clean up the mess in... 4a to the -2.

00:43

Think about this one as 4 times... big pause...

00:46

"a" to the -2.

00:49

That is, first get "a" to the -2 to be 1 over "a" squared.

00:54

That'll help simplify things a lot. And we then have 4 times that number...

00:58

which gives us 4 over "a" squared. Now that we've manipulated the inside of the

01:03

parentheses, we can work on the exponent.

01:05

So think of 4 over "a" squared as one unit for now, one thing that can't be changed...

01:10

for a moment anyway.

01:12

That whole chunk of number is now placed to the -1...

01:15

...which means that we take one OVER that number to then get rid of the negative exponent

01:19

thingy... which is just too odd to digest. So we have 1 OVER the quantity 4 over "a" squared.

01:26

Remember that dividing by a fraction is the same as multiplying the inverse -- so let's do that.

01:34

We get one TIMES "a" squared over 4. Which is just "a" squared over 4.

01:40

And ta-da.. the answer is B.

Up Next

CAHSEE Math 5.3 Algebra and Functions
2032 Views

CAHSEE Math: Algebra and Functions Drill 5, Problem 3. Solve the equation.

Related Videos

Simplifying Radicals
9737 Views

We don't like knocking people down to size, but we do like simplifying radicals. Join us?

Arithmetic Math
2248 Views

If fleeing criminals always fled the scene of the crime at perfect right angles, it would be much easier to determine their whereabouts. Fortunatel...

Basics of Game Theory
882 Views

Okay, so this probably isn't going to help you master Pokemon Go, but game theory can be applied to all sorts of situations. Even stomping your old...