3. The 3rd term of an A.P is 7 and 7th term is 15 then the first term

1.	3. The 3rd term of an A.P is 7 and 7th term is 15 then the first term is......
Answer» thank you so much bro given 3rd term of an AP=7 7th term of an AP=15 1st term of an AP=?Now, a+2d=7------------------(1) a+6d=15----------------(2) (1)-(2)=a+2d-(a+6d)=7-15 =a+2d-a-6d=-8 =-4d=-8 =d=2now,putting d=2 in (1) we have, =a+2.2=7 =a+4=7 =a=7/4

3. The 3rd term of an A.P is 7 and 7th term is 15 then the first term is......

Answer»

thank you so much bro

given 3rd term of an AP=7 7th term of an AP=15 1st term of an AP=?Now, a+2d=7------------------(1) a+6d=15----------------(2)

(1)-(2)=a+2d-(a+6d)=7-15 =a+2d-a-6d=-8 =-4d=-8 =d=2now,putting d=2 in (1) we have, =a+2.2=7 =a+4=7 =a=7/4