Ask your own question, for FREE!
Mathematics 8 Online
OpenStudy (anonymous):

H(x) with two complex solutions (completing the squares) please help

OpenStudy (amorfide):

Are we solving a function, or do you want us to make up a function?

OpenStudy (anonymous):

Makes a function @amorfide

OpenStudy (campbell_st):

its as simple as \[H(x) = x^2 + 1\] you can chek it by using the discriminant

OpenStudy (anonymous):

So the solution is (x+I)(x-I)? @ campbell_st

OpenStudy (amorfide):

No. you are thinking about difference of two squares if you were to have H(x)= x+2x+2 complete the square would be (x+1)^2 -1+2

OpenStudy (campbell_st):

nope the solution is set H(x) = 0 and solve for x so subtract 1 from both sides \[x^2 = -1\] then taking the square root of both sides \[x = \pm \sqrt{-1}\] which is a complex number and requires i^2 = -1 to simplify

OpenStudy (campbell_st):

so the next line becomes \[x = \pm \sqrt{1 \times i^2}\] after substituting... so now you can get your complex solution.

OpenStudy (campbell_st):

hope it makes sense

OpenStudy (campbell_st):

if you want a question that uses completing the square try H(x) = x^2 +4x + 12 complete the square in x H(x) = (x^2 + 4x + 4) + 8 then H(x) = (x + 2)^2 + 8 set H(x) = 0 and (x + 2)^2 + 8 = 0 subtract 8 from both sides (x + 2)^2 = -8 take the square root of both sides \[x + 2 = \pm \sqrt{-8}\] subtract 2 from both sides \[x = -2 \pm \sqrt{-8}\] use i^2 = -1 substitute and simplify

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!