+0

# Math help

0
222
3

Guest Apr 2, 2017
Sort:

#1
0

My question is this:

2 times the square root of 5

over------------------------------------------------------------------

2times the square root of 7 + 3 times the square root 3

Guest Apr 2, 2017
#2
+1

You should clarify your denominator. Is it 2sqrt(7) + 3sqrt(3)? Or, is it 2 sqrt(7+3) x sqrt(3)??

Guest Apr 2, 2017
#3
+82761
+1

2 sqrt (5) / [ 2 sqrt (7) + 3 sqrt (3) ]

Note that 2 sqrt (7) = sqrt (28)  and 3 sqrt (3)  = sqrt (27)

So we have

2 sqrt(5) / [ sqrt (28) + sqrt (27) ]

Multiply top/bottom by the conjugate of the denominator → [sqrt (28) - sqrt (27) ]]

And we have

[2 srqt (5)] [ sqrt (28) - sqrt (27)] / [  28 - 27 ]  =

[2 srqt (5)] [ sqrt (28) - sqrt (27)] / 1 =

[2 srqt (5)] [ sqrt (28) - sqrt (27)]   =

[2 sqrt (5)] [ 2 sqrt (7)  - 3 sqrt (3) ]=

4 sqrt (35)  - 6 sqrt (15)

CPhill  Apr 2, 2017

### 19 Online Users

We use cookies to personalise content and ads, to provide social media features and to analyse our traffic. We also share information about your use of our site with our social media, advertising and analytics partners.  See details