Write the first five terms of the sequences whose nth term is $$a_n=n\dfrac{n^2+5}{4}$$

Asked by Pragya Singh | 1 year ago |  76

##### Solution :-

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

$$a_1=1. \dfrac{1^2+5}{4}$$

$$a_1=\dfrac{6}{4}=\dfrac{3}{2}$$

$$a_2=2. \dfrac{2^2+5}{4}$$

$$a_2=\dfrac{18}{4}=\dfrac{9}{2}$$

$$a_3=3. \dfrac{3^2+5}{4}$$

$$a_3= \dfrac{42}{4}=\dfrac{21}{2}$$

$$a_4=4. \dfrac{4^2+5}{4}$$

$$a_4=\dfrac{84}{4}=21$$

$$a_5=5. \dfrac{5^2+5}{4}$$

$$a_5= \dfrac{150}{4}=\dfrac{75}{2}$$

Hence, the required terms are $$\dfrac{3}{2}$$, $$\dfrac{9}{2}$$,$$\dfrac{21}{2}$$ , 21 and $$\dfrac{75}{2}$$.

Answered by Abhisek | 1 year ago

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