Math, asked by zayn26, 1 year ago

if seventh term of an AP is 1/9 and its ninth term is 1/7 find its 63rd term

Answers

Answered by mysticd
19
Hi ,

Let a and d are first term and

Common difference of an A.P

It is given that ,

7th term = a 7= 1/9

a + 6d = 1/9 ---( 1 )

a9 = 1/7

a + 8d = 1/7 ----( 2 )

Subtract ( 2 ) from ( 1 ) we get,

2d = 2/63

d = 1/63 ---( 3 )

Put d = 1/63 in equation ( 1 ) ,

we get

a + 6/63 = 1/9

a + 2/21 = 1/9

a = 1/9 - 2/21

a = ( 7 - 6 )/63

a = 1/63

Therefore ,

63 rd term = a63

a63 = a + 62d

= 1/63 + 62/63

= ( 1 + 62 )/63

= 63/63

a63 = 1

I hope this helps you.

: )
Answered by TheLostMonk
5
◆◆◆◆

A7= 1/9

a + 6d = 1/9 ----(1)

A9 = 1/7

a + 8d = 1/ 7----(2)

subtract (1) from (2)

2d = 1/7 - 1/9

2d = 2 /63

d = 1/63

now put value of "d" in (1)

a + 6 × 1/63 = 1 /9

a = 1/ 9 - 6 / 63

a = 9 / 567

a = 1 / 63

now T63 = a + 62d

T63 = 1/ 63 + 62(1/63)

T63 = 63 /63 = 1

hence T63 = 1

◆hope it helps◆

TheLostMonk: what is the ans
zayn26: one
TheLostMonk: haha ,then why you marked him brainliest ,
TheLostMonk: you marked him brainliest because he ranked genius and he cannot do mistakes,but ,
zayn26: how to make ur solution brainliest
TheLostMonk: you can not make it correct , moderator calling me for correct my ans. but his ans is wrong
mysticd: yes , i did a mistake.
TheLostMonk: thankyou ,you corrected it , moderator were calling for me to correct by ans, 2-3 times he called
mysticd: Thank you .
TheLostMonk: ty ^_^
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