hello im working on a book on maths and i have come to a part i need help with.(adsbygoogle = window.adsbygoogle || []).push({});

(7-j4)(4-j3) is the equation i know that a^2-2ab+b^2 but what is the formula for abcd

the answer i have to get to is 28-j37-12 from what i know allready i got the 28 and the 12

so if you can help or explain it to me.

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# Homework Help: Find (7 - j4) (4 - j3) - complex numbers

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