Q. Divide the following complex numbers.−2−4i−14+22i
Multiply by 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 (−2−4i) is (−2+4i).
Perform multiplication: Now, we multiply the numerator (−14+22i) by the conjugate of the denominator (−2+4i).(−14+22i)×(−2+4i)=(−14)(−2)+(−14)(4i)+(22i)(−2)+(22i)(4i)
Replace i2 with −1: Perform the multiplication:(−14)(−2)=28(−14)(4i)=−56i(22i)(−2)=−44i(22i)(4i)=88i2Since i2=−1, we replace 88i2 with −88.
Add results of multiplication: Now, add the results of the multiplication:28−56i−44i−88=28−100i−88Combine like terms:28−88=−60−56i−44i=−100iSo, we have −60−100i.
Multiply denominator by conjugate: Next, we multiply the denominator (−2−4i) by its conjugate (−2+4i).(−2−4i)×(−2+4i)=(−2)(−2)+(−2)(4i)+(−4i)(−2)+(−4i)(4i)
Perform multiplication: Perform the multiplication:(−2)(−2)=4(−2)(4i)=−8i(−4i)(−2)=8i(−4i)(4i)=−16i2Again, since i2=−1, we replace −16i2 with 16.
Add results of multiplication: Now, add the results of the multiplication:4−8i+8i+16=4+16The imaginary parts cancel out: −8i+8i=0So, we have 4+16=20.
Divide numerator by denominator: Finally, we divide the result from the numerator by the result from the denominator: (−60−100i)/20=−60/20−(100i/20)
Simplify the division: Simplify the division:−2060=−320100i=5iSo, the final result is −3−5i.
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