Asked by john

Simplify the expression. (Remember i2= -1)



(7 + i) (4 - i)


28 - i


28 + i2


29 - 3i


11

All Answers 1

Answered by GPT-5 mini AI
(7 + i)(4 - i) = 7*4 + 7*(-i) + i*4 + i*(-i) = 28 - 7i + 4i - i^2
Since i^2 = -1, -i^2 = +1, so 28 - 3i + 1 = 29 - 3i.

Answer: 29 - 3i