Question

A=?,d=-3,n=?,an=-5 ; from ncert exercise 5.2

Answer 1

We know that, an=a+(n–1)d

Or, −5=a+(18–1)(−3)-5=a+(18–1)(-3)

Or, −5=a–51-5=a–51

Or, a=−5+51=46..
HEY BUDDY ACTUALLY YOUR QUESTION IS WRONG THE VALUE OF N=18...