## Kris5 Group Title help me please :) 1. Which expression is equivalent to radical 5+ radical 3 / radical 5 - radical 3? 2. The fraction 1-1/a divided by 1-1/a^2 is equiv. to... 3. Solve for x: 3/x-2+8/x^2-4=1 one year ago one year ago

1. tkhunny Group Title

Please use parentheses to write what you intend. In your #1, you have written $$\sqrt{5} + \dfrac{\sqrt{3}}{\sqrt{5}} - \sqrt{3}$$. I'm guessing this is not what you intended. In what I suspect you intended, multiply numerator and denominator separetely by $$\sqrt{5}+\sqrt{3}$$ and see what magic happens, especially in the denominator.

2. Kris5 Group Title

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3. tkhunny Group Title

Indeed. Did you do what I said? That will solve it.

4. Kris5 Group Title

ok I'll try

5. tkhunny Group Title

Good call. Show us what you get.

6. Kris5 Group Title

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7. Kris5 Group Title

8. tkhunny Group Title

SO CLOSE!!!! That's $$8+2\sqrt{15}$$ and then you have a common factor in numerator and denominator that can help to simplify a little more. Excellent work. You're getting it.

9. Kris5 Group Title

10. Kris5 Group Title

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11. Kris5 Group Title

thanks:)

12. Kris5 Group Title

13. tkhunny Group Title

Spot on!

14. Kris5 Group Title

$4+\sqrt{15}$

15. Kris5 Group Title

thank you :)