Q. Express as a complex number in simplest a+bi form:10−9i−19−iAnswer:
Multiply by Conjugate: To express the complex number (−19−i)/(10−9i) in simplest a+bi form, we need to eliminate the imaginary unit i from the denominator. We do this by multiplying the numerator and the denominator by the complex conjugate of the denominator.The complex conjugate of (10−9i) is (10+9i).
Expand Numerator: Now, we multiply both the numerator and the denominator by the complex conjugate (10+9i):((−19−i)⋅(10+9i))/((10−9i)⋅(10+9i))
Expand Denominator: We expand the numerator:(−19×10)+(−19×9i)+(−i×10)+(−i×9i)=−190−171i−10i+9=−181−181i
Divide Numerator by Denominator: We expand the denominator:(10×10)+(10×9i)+(−9i×10)+(−9i×9i)=100+90i−90i−81i2Since i2=−1, we have:=100−81(−1)=100+81=181
Separate Real and Imaginary Parts: Now we divide the simplified numerator by the simplified denominator: (−181−181i)/181
Combine Real and Imaginary Parts: We separate the real and imaginary parts and divide each by 181: Real part: −181/181=−1 Imaginary part: −181i/181=−i
Combine Real and Imaginary Parts: We separate the real and imaginary parts and divide each by 181:Real part: −181/181=−1Imaginary part: −181i/181=−iCombining the real and imaginary parts, we get the complex number in a+bi form:−1−i
More problems from Convert complex numbers between rectangular and polar form