Question

Which expression is equivalent to (4+3i)^2+(6-I)^2

Answer 1

Answer:

$\large\boxed{(4+3i)^2+(6-i)^2=42+12i}$

Step-by-step explanation:

$(4+3i)^2+(6-i)^2\qquad\text{use}\ (a\pm b)^2=a^2\pm2ab+b^2\\\\=4^2+2(4)(3i)+(3i)^2+6^2-2(6)(i)+i^2\\\\=16+24i+9i^2+36-12i+i^2\qquad i=\sqrt{-1}\to i^2=-1\\\\=16+24i+9(-1)+36-12i+(-1)\\\\=16+24i-9+36-12i-1\qquad\text{combine like terms}\\\\=(16-9+36-1)+(24i-12i)\\\\=42+12i$