Need Help Solving 2r^2 +2r+1= 0?

Thread starter Punchlinegirl
Start date Oct 15, 2006

AI Thread Summary

The equation 2r^2 + 2r + 1 = 0 cannot be factored easily, prompting the use of the quadratic formula to find its roots. The correct application of the formula leads to the calculation of roots as -0.5 ± i. There is a suggestion to ensure proper division and the use of parentheses for clarity in calculations. The discussion emphasizes the importance of understanding complex numbers in the context of quadratic equations. Overall, the conversation centers on solving the quadratic equation accurately.

Oct 15, 2006

Punchlinegirl

I'm feeling really stupid right now, but I can't seem to get this to factor.
2r^2 +2r+1= 0
Can someone please help me out?

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Oct 15, 2006

Hurkyl

Staff Emeritus

Science Advisor

Gold Member

You could factor it if you knew its roots, right?

Oct 15, 2006

Punchlinegirl

so to find the roots I'd use the quadratic formula
-2 +/- \sqrt 4-8 /4
so then would my roots be -.5 +/- 2i?

Oct 15, 2006

Hurkyl

Staff Emeritus

Science Advisor

Gold Member

I think you divided wrong. But you have the right idea. (And you should use parentheses when appropriate)

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