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# Radicals and rational exponents — Basic example

Watch Sal work through a basic Radicals and rational exponents problem.

## Want to join the conversation?

• Why did Sal stop saying “good luck test takers”
It was really a big time motivation
• Exam in 1 day and I dont know anything. sigh
• how did it go for you?
• Good luck to everyone on their SAT!
• Is there any way to practice this on here because that is what I really need to do.
• If you multiply the same square root with itself does it always just give you the number? For eg. (sqroot 2) * (sqroot 2) = 2.
• Yes. When you take the square root of something, you ask "What number multiplied by itself gives me my input?". When you take this number and multiply it by itself, like in the equation you so kindly provided, by definition you should get the input.
• if sqroot times sqroot is a whole number then how come when he multiplied the decimals in the sqroots it didn't come out as 0.5 but as a root 0.5
• You don't quite have it down.

Like Sal shows sqrt(a) * sqrt(b) = sqrt(a * b).

If both radicals are the same (a = b), then your case will be true. e.g.:
sqrt(4) * sqrt(4) = sqrt(4 * 4) = 4

I believe you were thinking of perfect squares, such as the example I just gave.

Hope this helps!
- Convenient Colleague
• Help🥲😭
• why didn't we multiply 3 and 1/3 to get 1 what...