Question 31240: Hello,
I have another question from my practice math exam, please help!
(8)^2/3 (16)^1/4=
-Thanks
Kristin
Answer by longjonsilver(2297) (Show Source):
You can put this solution on YOUR website! means either or . You can solve either. However, the first version has which is 64 then we need to find a cube root of that etc... Going the way of "increasing the numbers" is more difficult.
My approach would always be to do the fractional power first if possible, to keep the numbers smaller:
since 2*2*2 = 8
--> 
--> 4
means what number multplied to itself 4 times is 16? Answer is 2:
2*2*2*2 = 16
You need to recognise the following, in relation to powers:
2: 2,4,8,16,32,64,128,256,512,1024
3: 3,9,27,81
4: 4,16,64
5: 5,25,125,625
6: 6,36,216
7: 7,49,343
8: 8,64,512
9: 9,81,729
Recognise these numbers at least. Learn them if possible. That way you can answer the following type of Q really confidently:
means --> --> 49
jon.
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