SOLUTION: solve by using quadratic formula t^2 + 2t + 2 = 0

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Question 134353: solve by using quadratic formula
t^2 + 2t + 2 = 0
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Let's use the quadratic formula to solve for t:


Starting with the general quadratic

at%5E2%2Bbt%2Bc=0

the general solution using the quadratic equation is:

t+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29



So lets solve t%5E2%2B2%2At%2B2=0 ( notice a=1, b=2, and c=2)




t+=+%28-2+%2B-+sqrt%28+%282%29%5E2-4%2A1%2A2+%29%29%2F%282%2A1%29 Plug in a=1, b=2, and c=2



t+=+%28-2+%2B-+sqrt%28+4-4%2A1%2A2+%29%29%2F%282%2A1%29 Square 2 to get 4



t+=+%28-2+%2B-+sqrt%28+4%2B-8+%29%29%2F%282%2A1%29 Multiply -4%2A2%2A1 to get -8



t+=+%28-2+%2B-+sqrt%28+-4+%29%29%2F%282%2A1%29 Combine like terms in the radicand (everything under the square root)



t+=+%28-2+%2B-+2%2Ai%29%2F%282%2A1%29 Simplify the square root (note: If you need help with simplifying the square root, check out this solver)



t+=+%28-2+%2B-+2%2Ai%29%2F%282%29 Multiply 2 and 1 to get 2


After simplifying, the quadratic has roots of

t=-1+%2B+i or t=-1+-+i