Write the first five terms of the sequences whose nth term is an = (-1)n-1 5n+1

Asked by Pragya Singh | 1 year ago |  70

##### Solution :-

Given nth term, an = (-1)n-1 5n+1

On substituting n = 1, 2, 3, 4, 5, we get

$$a_1=(-1)^{1-1}5^{1+1}$$

$$a_1=5^2-25$$

$$a_2=(-1)^{2-1}5^{2+1}$$

$$a_2=-5^3=-125$$

$$a_3=(-1)^{3-1}5^{3+1}$$

$$a_3=5^4=625$$

$$a_4=(-1)^{4-1}5^{4+1}$$

$$a_4=-5^5=-3125$$

$$a_5=(-1)^{5-1}5^{5+1}$$

$$a_5=5^6=15625$$

Hence, the required terms are 25, –125, 625, –3125, and 15625.

Answered by Abhisek | 1 year ago

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