Question

If 3rd term, 6th term and last term of an ap is 6, 48 and 3072 respectively, find first term and no. Of terms

Answer 1

Answer:

Step-by-step explanation: we have,

3rd term=> a+2d =6......(1)

4th term=> a +3d=48.......(2)

Last term=>an= 3072.......(3)

Now,

(2)-(1)=>d =42

So,(1)=>a=6-2d =6-2×42= -78

Now ,

(3)=>a+(n-1)d =3072 which is the reqd. No. of terms.

And the reqd ap is....a,a+d,....