Question

помогите решить 9) и 10)
тема: комплексные числа

Answer 1

$9) frac{1-3i}{-2+i}+ frac{1+4i}{-1+3i} =\ =frac{(1-3i)(-2-i)}{5}+ frac{(1+4i)(-1-3i)}{10} =\ =frac{-2+6i-i+3i^2}{5}+ frac{-1-4i-3i-12i^2}{10} =\ =frac{-10+10i}{10}+ frac{11-7i}{10} =\ = frac{1+3i}{10}$

$10) frac{a+bi}{a-bi} - frac{a-bi}{a+bi} =\ = frac{a^2-b^2+2abi-a^2+b^2+2abi}{a^2+b^2} =\ = frac{4abi}{a^2+b^2}$