Question

(3a - 2b - 5c)^2 expand this step by step
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Answer 1

Answer:

9a^2 + 4b^2 + 25c^2 - 12ab + 20bc - 30ca

Step-by-step explanation:

(3a - 2b - 5c )^2

using identity _ (a^2+b^2+c^2)=

a^2 + b^2 + c^2 + 2ab + 2bc + 2ca

= (3a)^2 + (-2b)^2 + (-5c)^2 + 2(3a)(-2b) + 2(-2b)(-5c) + 2(-5c)(3a)

= 9a^2 + 4b^2 + 25c^2 - 12ab + 20bc - 30ca

answer