Check this please

(5a^3 – 4a – 5) + (2a^3 – 2a + 3)

=(5a^3 +2a^3)+(-4a-2a)+(-5+3)

=(5a^3 + 2a^3) + [-4a(-2a)] + [-5+3]

=[(5-2)a^3] + [(-4-2)a] +[-5+3]

=3a^3 + (-6a) +(-2)

=3a^3-6a-2
 
=(5a^3 + 2a^3) + [-4a(-2a)] + [-5+3]

= ( (5+2) a^3) ........rest is correct
 
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