SOLUTION: In physics class, Taras discovers that the behavior of electrical power, x, in a particular circuit can be represented by the function f(x)=x^2+2x+7/ If f(x)=0, solve the equation

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Question 246686: In physics class, Taras discovers that the behavior of electrical power, x, in a particular circuit can be represented by the function f(x)=x^2+2x+7/ If f(x)=0, solve the equation and express your answer in simplest a + bi form.
please help me solve this problem Please show work thank you
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
f(x)=x^2+2x+7/ If f(x)=0, solve the equation and express your answer in simplest a + bi form
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Solved by pluggable solver: SOLVE quadratic equation (work shown, graph etc)
Quadratic equation ax%5E2%2Bbx%2Bc=0 (in our case 1x%5E2%2B2x%2B7+=+0) has the following solutons:

x%5B12%5D+=+%28b%2B-sqrt%28+b%5E2-4ac+%29%29%2F2%5Ca

For these solutions to exist, the discriminant b%5E2-4ac should not be a negative number.

First, we need to compute the discriminant b%5E2-4ac: b%5E2-4ac=%282%29%5E2-4%2A1%2A7=-24.

The discriminant -24 is less than zero. That means that there are no solutions among real numbers.

If you are a student of advanced school algebra and are aware about imaginary numbers, read on.


In the field of imaginary numbers, the square root of -24 is + or - sqrt%28+24%29+=+4.89897948556636.

The solution is , or
Here's your graph:
graph%28+500%2C+500%2C+-10%2C+10%2C+-20%2C+20%2C+1%2Ax%5E2%2B2%2Ax%2B7+%29

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x = -1 ± i*sqrt(6)