solve this in paper and send please
Attachments:
Answers
Answered by
5
Given:
a4+a8=24
Now,
➡a+3d+a+7d=24
➡2a+10d=24
➡a+5d=12-----------(1)
Also,
➡a6+a10=44
➡a+5d+a+9d=44
➡2a+14d=44
➡a+7d=22------------(2)
Subtracting equation (2) from (1),
↪ -2d= -10
↪ d=5
Substituting this value of d in eq(1),
↪a+5(5)=12
↪a+25=12
↪a=12-25
↪a= -13
a=-13 and d=5
Hence, the first three terms of the AP will be:
↪a=-13
↪a+d=-13+5=-8
↪a+2d=-13+2(5)=-13+10=-3
➡-13,-8,-3..
Answered by
8
Let the first term be 'a' and common difference be 'd' .
Given ,
4th term + 8th term = 24
=> a + 3d + a +7d = 24
=> 2a + 10d = 24
=>2 (a+5d)= 2×12
=> a + 5d = 12 ------------> i
and ,
6th term + 10th term = 44
=> a+ 5d + a + 9d = 44
=> 2a + 14d = 44
=> a + 7d = 22---------> ii
Now ,
ii- i
=> a+7d -(a + 5d) = 22-12
=> a + 7d - a - 5d = 10
=> 2d = 10
=> d = 5
again ,
using d = 5 in (i) we have ,
=> a + 5×5 = 12
=> a = 12 - 25
=> a = -13
So , terms of AP are
-13 ,-13+5 , -13 + 2×5 , -13 + 3×5 , .................-13 + (n -1) 5
= -13 ,-8,-3,2 ,..............-13+(n-1)5
Given ,
4th term + 8th term = 24
=> a + 3d + a +7d = 24
=> 2a + 10d = 24
=>2 (a+5d)= 2×12
=> a + 5d = 12 ------------> i
and ,
6th term + 10th term = 44
=> a+ 5d + a + 9d = 44
=> 2a + 14d = 44
=> a + 7d = 22---------> ii
Now ,
ii- i
=> a+7d -(a + 5d) = 22-12
=> a + 7d - a - 5d = 10
=> 2d = 10
=> d = 5
again ,
using d = 5 in (i) we have ,
=> a + 5×5 = 12
=> a = 12 - 25
=> a = -13
So , terms of AP are
-13 ,-13+5 , -13 + 2×5 , -13 + 3×5 , .................-13 + (n -1) 5
= -13 ,-8,-3,2 ,..............-13+(n-1)5
Similar questions