Respuesta :
Answer:
No real root.
Complex roots:
[tex] x = -1 \pm 2i [/tex]
Step-by-step explanation:
[tex] x^2 + 2x = -5 [/tex]
[tex] x^2 + 2x + 5 = 0 [/tex]
There are no two integers whose product is 5 and whose sum is 2, so this trinomial is not factorable. We can use the quadratic formula.
[tex] x = \dfrac{-b \pm \sqrt{b^2 - 4ac}}{2a} [/tex]
[tex] x = \dfrac{-2 \pm \sqrt{2^2 - 4(1)(5)}}{2(1)} [/tex]
[tex] x = \dfrac{-2 \pm \sqrt{4 - 20}}{2} [/tex]
[tex] x = \dfrac{-2 \pm \sqrt{-16}}{2} [/tex]
Since we have a square root of a negative number, there are no real roots. If you have learned complex numbers, then we can continue.
[tex] x = \dfrac{-2 \pm 4i}{2} [/tex]
[tex] x = -1 \pm 2i [/tex]
Answer: -1 +/- 2i (read -1 plus or minus 2i).
Using the quadratic formula given that a=1, b=2, c=5, the roots are:
(-2 +/- sqrt(4-4(1)(5)))/(2*1)= (-2 +/- sqrt(-16))/2= (-2 +/- 4i)/2.
Using the quadratic formula given that a=1, b=2, c=5, the roots are:
(-2 +/- sqrt(4-4(1)(5)))/(2*1)= (-2 +/- sqrt(-16))/2= (-2 +/- 4i)/2.