Find the 20th term of the series 2 × 4 + 4 × 6 + 6 × 8 + … + n terms.

Asked by Pragya Singh | 1 year ago |  89

##### Solution :-

Given series is 2 × 4 + 4 × 6 + 6 × 8 + … n terms

nth term = a= 2n × (2n + 2) = 4n2 + 4n

The 20th term,

a20 = 4 (20)2 + 4(20) = 4 (400) + 80 = 1600 + 80 = 1680

Therefore, the 20th term of the series is 1680.

Answered by Abhisek | 1 year ago

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