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If y= square root of 0.36x^8, then y =
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21 Jun 2017, 02:19
21 Jun 2017, 02:19
Expert Reply
00:00
Question Stats:
82% (00:35) correct
17% (00:30) wrong based on 67 sessions
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If \(y= \sqrt{0.36x^8}\), then y =
A) \(0.06x^2\)
B) \(0.06x^4\)
C) \(0.06x^5\)
D) \(0.6x^2\)
E) \(0.6x^4\)
Re: If y= square root of 0.36x^8, then y =
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01 Feb 2018, 11:19
01 Feb 2018, 11:19
1
y=sq. root(0.36*x^8) or, y= sq. root(((6/10)*x^4)^2) or, y= 0.6*x^4
So the answer is E.
So the answer is E.
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Re: If y= square root of 0.36x^8, then y =
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01 Feb 2018, 13:30
01 Feb 2018, 13:30
2
Expert Reply
If y= √(0.36x^8), one way to simplify it would be to split the roots so y = √(.36)√(x^8). Then we can take the square root of them separately. The square root of .36 is .6, since the square root of 36 is 6 and if I need to generate two decimals in the square, I need one decimal in the square root. To put it another way, .6^2 will be .36, since when you multiply two numbers with one decimal place each, the resulting number should have 2 decimals. Now for the second part: √(x^8) must be x^4. To take the square root of any number with an exponent, simply divide the exponent in half. Thus the 8 becomes a 4.
So at the end of all this we have y = .6x^4, or E.
Another way we could've approached this problem is to look at the answer choices and square all of them. Whichever one winds up being the same as everything under the radical must be the correct answer.
So at the end of all this we have y = .6x^4, or E.
Another way we could've approached this problem is to look at the answer choices and square all of them. Whichever one winds up being the same as everything under the radical must be the correct answer.
