About this video
Sal finds the value of 5 to the third power. He stresses that 5^3 means 5 multiplied by itself three times (5 x 5 x 5 = 125), not 5 times 3, which means adding 5 to itself three times (15).
You'll be able to
- explain what an exponent means.
- evaluate a number raised to the third power.
- tell the difference between 5^3 and 5 x 3.
Key words
- exponent
- The small raised number that tells you how many times to multiply the base by itself.
- third power
- Multiplying a number by itself three times, like 5 x 5 x 5.
Transcript
Find the value of 5 to the third power. Let me rewrite that. We have 5 to the third power. Now, it's important to remember, this does not mean 5 times 3. This means 5 times itself three times, so this is equal to 5 times 5 times 5. 5 times 3, just as a bit of a refresher so you realize the difference, 5 times 3-- let me write it over here.
5 times 3 is equal to 5 plus 5 plus 5. So when you multiply by 3, you're adding the number to itself three times. When you take it to the third power, you're multiplying the number by itself three times. So 5 times 3, you've seen that before, that's 15. But 5 to the third power, 5 times itself three times, is equal to-- well, 5 times 5 is 25, and then 25 times 5 is 125, so this is equal to 125.
And we're done!
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