Question

I have this problem: http://i.imgur.com/CQphj.png
When i solve it i get 5b^3. How do i solve this?

Answer 1

could you draw your solution here?

Answer 2

After i simplify each one i get 6b^3 + 4b^3 -5b^3 which simplifies down into 5b^3
Is that enough or should i actually draw it?

Answer 3

no...i saw your mistake already :)

Answer 4

\[\Huge \sqrt{b^3} \implies \sqrt{b^2 \times b} \implies \sqrt{b^2} \times \sqrt b\] do you agree with this?

Answer 5

Yeah

Answer 6

and do you agree that \[\LARGE \sqrt{b^2} = b?\]

Answer 7

Yes

Answer 8

therefore
\[\huge \sqrt{b^2} \times \sqrt{b} \implies b \times \sqrt b \implies b\sqrt b\]

Answer 9

do you see where im getting at?

Answer 10

Oh. Yeah, i get it.

Answer 11

great :D

Answer 12

so when you root the numbers and variables stay separate?

Answer 13

what do you mean?

Answer 14

So \[\sqrt{36b^3} = 6\sqrt{b^3}\] ?

Answer 15

but remember \(\sqrt{b^3} = b\sqrt b\) therefore \[\LARGE \sqrt{36b^3} = 6b\sqrt b\]

Answer 16

same with the others

Answer 17

I get it now. Thanks :)

Answer 18

great :DDD

Answer 19

Can you help me with one more? http://i.imgur.com/aQGov.png

Answer 20

I dont really understand what to do with the fraction.

Answer 21

Do you make both of the denominators the same or how do you do it?