How do you multiply (5-12i)(2+3i) (5−12i)(2+3i) in trigonometric form?

1 Answer
Mia
Nov 20, 2016

=46-19i=46−19i

Explanation:

Expanding these factors is determined by applying Distributive property.
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Distributive Property:
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color(blue)((a+b)(c+d) = axxc + axxd + bxxc + bxxd)(a+b)(c+d)=a×c+a×d+b×c+b×d
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(5 - 12i)(2 + 3i) (5−12i)(2+3i)
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=color(blue)(5xx2 + 5xx3i +(-12i)xx2 + (-12ixx3i))=5×2+5×3i+(−12i)×2+(−12i×3i)
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=10 + 5i -24i -36i^2=10+5i−24i−36i2
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=10 -19i-36xx-1" "=10−19i−36×−1 As we know " "i^2=-1 i2=−1
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=10-19i+36=10−19i+36
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=46-19i=46−19i

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