Answer: 49+64i
Explanation:
Concept to know:
i=√-1
i²=-1
i³=-i
=1
-------------------------------------
(-5+8i)(3-8i)
=-15+40i+24i-64i²
=-15+64i-64i²
=-15+64i+64 (remember, i²=-1)
=49+64i
Hope this helps!! :)
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