Q. Divide the following complex numbers.4−3i10−20i
Find Conjugate: To divide complex numbers, we multiply the numerator and denominator by the conjugate of the denominator. The conjugate of a complex number a+bi is a−bi. So, the conjugate of 4−3i is 4+3i.
Multiply Numerators: Multiply the numerator (10−20i) and the denominator (4−3i) by the conjugate of the denominator (4+3i).(10−20i)×(4+3i)/(4−3i)×(4+3i)
Multiply Denominators: First, we'll multiply out the numerators:(10−20i)×(4+3i)=10×4+10×3i−20i×4−20i×3i=40+30i−80i−60i2Since i2=−1, we replace −60i2 with 60.=40+30i−80i+60=100−50i
Simplify Numerator and Denominator: Now, we'll multiply out the denominators:(4−3i)×(4+3i)=4×4+4×3i−3i×4−3i×3i=16+12i−12i−9i2Again, since i2=−1, we replace −9i2 with 9.=16+12i−12i+9=16+9=25
Divide Numerator by Denominator: Now we have the simplified numerator and denominator:Numerator: 100−50iDenominator: 25We divide the numerator by the denominator:25100−50i
Final Simplified Form: Divide both the real part and the imaginary part of the numerator by the denominator:25100−2550i= 4−2iThis is the simplified form of the division of the complex numbers.
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