## hogie 2 years ago Simplifying radical expressions.

1. hogie

$\sqrt{4a^2}$

2. hogie

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3. hogie

What do i do with the a^2

4. hogie

?

5. hogie

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6. dave0616

a is squared, and the opposite of a square root is to the second power. because this expression can also be written as (4a^2)^1/2. so if you take 2 and multiply it by a half, you get 1. so the answer is 2a

7. hogie

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8. dave0616

same principle is used. (4x^4)^1/2, 4*(1/2)=2= 2x^2

9. hogie

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10. dave0616

correct

11. hogie

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12. dave0616

13. hogie

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14. hogie

you can only pull two x's out right?

15. dave0616

that is correct. so now you have sqrt(x^4). well in a way yes, but lets go ahead and use the formula we had.: (x^4)^1/2 4*(1/2)=2

16. dave0616

so you have x^2

17. hogie

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18. hogie

That would be the answer? ^^^

19. dave0616

nope, because you origonally had :$\sqrt{x^{4}}$ and you took the square root of that to get x^2

20. hogie

So what would it be? Just x^2

21. hartnn

$$\large \sqrt{9x^4}= 3x^2$$ is correct.

22. dave0616

@hartnn and @hogie i guess i am confused as to where the sqrt(9x^4) came from, because i dont see that any where, thought 3x^2 would be correct for that

23. hartnn

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24. dave0616

ohhhh i mistook that as a four, im sorry, then yes 3x^2 would be correct