Question

5. Which term of the given AP
2,-1,-4, -7, ... is -40?​

Answer 1

Answer:

15th of the given AP will be -40

Step-by-step explanation:

AP : 2,-1,-4, -7, ...   (given)

Here,

a=2 and d=-3

let -40 be $n^{th}$ term

n=?

$a_{n}$= -40

We know that ,

$a_{n}$= a+(n-1)d

⇒a+(n-1)d= -40

⇒2+(n-1)(-3)= -40

⇒(n-1)(-3)= (-40-2)

⇒(n-1)= (-42)/(-3)

⇒n=14+1

∴n=15