Nov
24
Explain how to do this math problem? Tell me how to do this, not the answer.?
By
I want to know how to do this instead of just asking for the answers. Can you help me with this?
Here are some of the things that will be on the study guide.
sqrt of 45 + sqrt of 80 = ? –
sqrt of 45
________ –In case you didnt know, thats a division problem.
sqrt of 81
One more.
2*sqrt of 18 * 3*sqrt of 28
Please help me I have a math test coming up and am freakin out!
2 Comments
November 24th, 2009 at 6:35 am
For the first one sqrt 45 + sqrt 80, if you square them both then you just end up with 45 + 80 which =125 Now all you have to do is sqrt it again because you squared it to begin with so the answer is sqrt 125. Leave the answer like this, it’s in its most accurate form.
Second one, again sqauare them both so you have 45 over 81 then put a large square root sign over then entire thing, because you need to sqrt it all since you squared it all to begin with
last one square it all again so you have 2*18 * 3*28
so then you have 36*84 which = 3024, then again because you squared at the beginning, sqrt the answer so answer is sqrt 3024
Hope my help was clear enough for you
November 24th, 2009 at 7:05 am
wish I knew how to make square root sign – alas
but (yadayadayada)^.5 works just as well…
AJ’s first paragraph is completely wrong !
[x+y]^.5 DOES NOT EQUAL x^.5 + y^.5 !!!
Recall that [x*y]^.5 = x^.5 * y^.5
Also [x/y]^.5 = {[x]^.5}/y^.5
[45]^.5 + [80]^.5 =[9*5]^.5 + [16*5]^.5 =
= 3[5]^.5 + 4[5]^.5 = 7[5]^.5
[45]^.5 / [81]^.5 = [9*5]^.5 / 9 = [9]^.5 * [5]^.5 / 9 = 3 [5]^.5 / 9 = [1/3][5]^.5
2[18]^.5 * 3[28]^.5 = 2*3*[18*28]^.5 = 6 [9*2*7*4]^.5 = 6[36]^.5 * [14]^.5 = 6*6[14]^.5 that is to say the root 14 doesn’t simplify out