a) What is the sum of: (3−4i) and (−21−6i)?1) −24−10i2) 18−2i3) −18−10i4) 24+2ib) Simplify 2−3i2+2i1) −124; −(54)i2) −124; +(54)i3) 122; −122; i4) 122; +122;i

Question

a) What is the sum of: (3−4i) and (−21−6i)?1) −24−10i2) 18−2i3) −18−10i4) 24+2ib) Simplify 2−3i2+2i1) −124; −(54)i2) −124; +(54)i3) 122; −122; i4) 122; +122;i

Misurina6am · Accepted Answer

Step 1If z1=x1+iy1 and z2=x2+iy2 are two complex number then sum of this complex number is.z=z1+z2z=(x1+x2)+i(y1+y2)Here given thatz1=(3−4i); z2=(−21−6i)then z=z1+z2⇒z=(3−4i)+(−21−6i)⇒z=3−4i−21−6i⇒z=(3−21)−i(4−6)⇒z=−18−10iHere optim think is correct answer.

stadfeste8ru · Accepted Answer

Step 1b) Given that: 2−2i2+2iWe multiply of (2−2i) in this denominator and numerator then⇒2−2i2+2i×(2−2i)(2−2i)=2(2−2i)−3i(2−2i)(2)2−(2i)2{∵(a+b)(a−b)=(a2−b2)⇒4−4i−6i+6i24−(4i2)=4+6i2−10i4−4i2 {∵i2=−1}⇒4−6−10i4−4(−1)=−2−10i4+4=−28−10i8=(−14−54i)

a) What is the sum of: \(\displaystyle{\left({3}-{4}{i}\right)}\)

Answered question

Answer & Explanation

New Questions in Algebra II