Question

complete steps of expansion (2x+3y+4z)2 pls help me
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Answer 1

(2x+3y+4z)
2


=(2x)
2
+(3y)
2
+(4z)
2
+(2×2x×3y)+(2×3y×4z)+(2×4z×2x)

(∵(a+b+c)
2
=a
2
+b
2
+c
2
+2ab+2bc+2ca)

=4x
2
+9y
2
+16z
2
+12xy+24yz+16zx

Hence, (2x+3y+4z)
2
=4x
2
+9y
2
+16z
2
+12xy+24yz+16zx.