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If $p^{3} + 3p^{2} + 3p = 7,$ then the value of $p^{2} + 2p$ is :

1. $1$
2. $3$
3. $5$
4. $15$

Given that: $p^3+3p^2+3p=7$,put $p=1$ we will get LHS=RHS,for $p=1$ given equation satisfied.

so the value of $p^2+2p=1+2=3$

Option (B) is correct.
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(p+1)^3 = p^3 + 1 + 3p(p+1)

=[p^3+3p^2+3p] + 1

=7+1=8

therefore p+1=2 => p=1

34 points

1
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