Question

fcucyfta12=37,d=3, find a and sum of n term​

Answer 1

Answer:

$\huge{\red{\boxed{\boxed{\green{\sf{a=4,Sn=\frac{5n+3n^{2}}{2}}}}}}}$

Step-by-step explanation:

$\huge{\red{\boxed{\boxed{\green{\underline{\red{\sf{SOLUTION-}}}}}}}}$

□a12=27

□d=3

To find:

□a=?

□Snth term=?

$a12 = 37 \\ = )a + 11d = 37 \\ = )a + 11 \times 3 = 37 \\ = )a + 33 = 37 \\ = )a = 37 - 33 \\ = )a = 4 \\ \\ sn = \frac{n}{2} (2a + (n - 1)d) \\ = ) \frac{n}{2} (2 \times 4 + (n - 1) \times 3) \\ = ) \frac{n}{2} (8 + 3n - 3) \\ = ) \frac{n}{2} (5 + 3n) \\ = ) \frac{5n + 3 {n}^{2} }{2}$

$\huge{\red{\boxed{\boxed{\green{\sf{a=4,Sn=\frac{5n+3n^{2}}{2}}}}}}}$

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