Question: Root in the Denominator

Comment on Root in the Denominator

calculation on 01:27 is not clear. Am adding 2+2-1-3 should give me 0 not -1. please explain how you got the -1 when you simplify. thanks
greenlight-admin's picture

When simplifying expressions, we need to add like terms.
For example, 2x + 2y - y - 3x simplifies to be x - y. We combine the 2x and -3x separately and we must combine 2y and -y separately.
You are combining ALL of the terms.

So, when simplifying 2 + 2√3 - √3 - 3, we must combine the two like terms 2√3 and -√3. We get 1√3.
Then we combine 2 and -3 to get -1
So, altogether, 2 + 2√3 - √3 - 3 = -1 + √3
Does that help?

do you believe we have enough time on the test day to perform such calculations?
greenlight-admin's picture

Yes, you should have enough time . . . as long as it doesn't take you too long to see what steps are required.

Please which module did you teach conjugate roots
greenlight-admin's picture

It's lesson #29 in this module. Here's the link:


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