Multiply by conjugate: To divide complex numbers, we multiply the numerator and denominator by the conjugate of the denominator. The conjugate of (3+i) is (3−i).3+i−8−6i×3−i3−i
Multiply numerators and denominators: Now, we multiply the numerators together and the denominators together.Numerator: (−8−6i)(3−i)Denominator: (3+i)(3−i)
Multiply out the numerator: First, we'll multiply out the numerator.(−8−6i)(3−i)=−8⋅3−8⋅(−i)−6i⋅3−6i⋅(−i)=−24+8i−18i+6i2Since i2=−1, we replace i2 with −1.=−24−10i+6(−1)=−24−10i−6=−30−10i
Multiply out the denominator: Next, we'll multiply out the denominator.(3+i)(3−i)=3⋅3+3⋅(−i)+i⋅3−i⋅i=9−3i+3i−i2Again, since i2=−1, we replace i2 with −1.=9−1=8
Simplify numerator and denominator: Now we have the simplified numerator and denominator.Numerator: −30−10iDenominator: 8We divide the numerator by the denominator.(−30−10i)/8
Divide numerator by denominator: Divide both the real part and the imaginary part by 8. Real part: −30/8=−3.75Imaginary part: −10i/8=−1.25iSo the division gives us −3.75−1.25i.
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