# Algebra

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I had to solve 2x^2-x-1 using the quad. formula. I got it down to (1 +/- the square root of neg. 8) divided by four. I broke the sq. of neg. 8 into the sq. root of 4 and the sq. root of -2. But my question is could it also be the sq. root of -4 and the sq. root of two? Is one way right or wrong? And when I go from there, I reduced this to 1+/-2 times the sq. root of 2i/4. I further reduced it to 1/4 +/- 1/2 the sq. root of i/2. But I'm not sure if I reduced it properly. Could you show me? Thank you!

• Algebra -

Doublecheck the expression within the square root, and watch your signs.

b^2 - 4ac

1 - (4)(1)(-1)

• Algebra - oops typo -

b^2 - 4ac

1 - (4)(2)(-1)

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