Question

a=1/2,d=3/2 then what is the Tn=40 in AP​

Answer 1

Step-by-step explanation:

$Tn = a + (n - 1)d \\ = > 40= \frac{1}{2} + (n - 1) \times \frac{3}{2} \\ = > 40 = \frac{1}{2} + \frac{3}{2} n - \frac{3}{2} \\ = > \frac{3}{2} n = 40 + \frac{3}{2} - \frac{1}{2} \\ = > \frac{3}{2} n = \frac{40 + 3 - 1}{2} \\ = > \frac{3}{2} n = \frac{42}{2} \\ = > 3n = 42 \\ = > n = \frac{42}{ =3} \\ = > n = 14$