Question

find AP whose nth term is 7-3n. also find the 20th term​

Answer 1

your answer

nth term =7-3n

1st term =7-3*1=4

similary

20th term =7-60=-53

Answer 2

use the formula (an-1 - an=d)

or (an = a+(n-1)d )

ex: an=a+(n-1)d using this formula

a=7

let n=2

then a 2=9

then now d=2

now substitute in formula

7+(2 -1)2=7+2=9

now a=9

then substitute in formula  

9+(2-1)2=11

like this until 20th term u have 2 do