9514 1404 393
Answer:
x = -0.25+√2.4375i or -0.25-√2.4375i
Step-by-step explanation:
The quadratic formula works for this. The quadratic equation ...
ax² +bx +c = 0
has solutions given by the quadratic formula:
[tex]x=\dfrac{-b\pm\sqrt{b^2-4ac}}{2a}[/tex]
Your equation ...
2x² +x +5 = 0
has coefficients a=2, b=1, c=5, so the quadratic formula tells you the solutions are ...
[tex]x=\dfrac{-1\pm\sqrt{1^2-4\cdot2\cdot5}}{2\cdot2}=\dfrac{-1\pm\sqrt{-39}}{4}\\\\x=\left\{-\dfrac{1}{4}+\dfrac{\sqrt{39}}{4}i, -\dfrac{1}{4}-\dfrac{\sqrt{39}}{4}i\right\}[/tex]
The decimal equivalents are ...
x = -0.25+√2.4375i or -0.25-√2.4375i . . . . . . the 'i' is outside the radical
