Q. Prove that 1.3+2.4+3.5+....+n(n+2) = 1/6n (n+1) (2n+7),~~V~~ nEN.

Hi!

Here is the proof to your question.

Let P (

*n*): 1 × 3 + 2 × 4 + 3 × 5 + ... +*n*(*n*+ 2)Now, 1 × 3 = 3

Also,

∴P (

*k*+ 1) is true.So, by method of induction it can be said that P (

*n*) is true for*n*ε**N**Hope! This will be helpful for you.

Cheers!!!

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