Question

if nth term is 5 +( n - 1) 3 then find 20th term​

Answer 1

Answer:

the and is 72

Step-by-step explanation:

hope it helps you

marked as brain list answer

Answer 2

Answer: 63

Step-by-step explanation:

So here's how we do it.

an = 5+(n-1)3

So,

a+(n-1)d = 5+(n-1)3

a+nd-d = 5+3n-3

a+nd-d = 3n+2 ----------------------(1)

nd+(a-d) = 3n+2 ---------------------(2)

Comparing 1 and 2:

we get,

d = 3

a-d = 3

a20 = a+(n-1)d

a20 = a+nd-d

a20 = nd+(a-d)

a20 = 20×3+3

a20 = 60+3 = 63

Hope it helps.