Simplifying rational expressions (old video)
About this video
Sal simplifies 28b^6 divided by 7b. He splits it into 28/7 times b^6/b, simplifies 28/7 to 4, and uses the exponent rule b^6 / b^1 = b^(6-1) = b^5 to get 4b^5.
You'll be able to
- split a quotient of monomials into a number part and a variable part.
- divide powers with the same base by subtracting exponents.
- simplify 28b^6 / 7b to 4b^5.
Key words
- exponent
- The power a base is raised to, like the 6 in b^6.
- quotient
- The result of dividing one quantity by another.
- b to the first
- Just b; a variable with no written exponent has exponent 1.
Transcript
Simplify the expression 28b to the sixth divided by 7b. Well this is the same thing as 28/7 times b to the sixth over b. And I did it this way so that we have b to the sixth over b to some other power. And this is over b, which is the same thing as b to the first.
So we could simplify this using exponent properties. And 28/7 we can just clearly simplify because 28 is divisible by 7. 28 divided by 7 is just 4. So that is just 4. And then b to the sixth divided by b to the one, that's just going to be b to the sixth minus 1 power.
So times b to the sixth minus 1 or b to the fifth. So our answer is 4b to the fifth.
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