Let a 1 , a 2 , a 3 , … , be a G . P . such that a 1 < 0 , a 1 + a 2 = 4 and a 3 + a 4 = 16 . If ∑ i = 1 9 a i = 4 λ , then λ , is equal to.

Question

Let a 1 , a 2 , a 3 , &#8230; , be a G . P . such that a 1 &#60; 0 , a 1 + a 2 = 4 and a 3 + a 4 = 16 . If &#8721; i = 1 9 a i = 4 &#955; , then &#955; , is equal to.

Aicharya · Accepted Answer

a 1 + a 2 = 4 &#8658; a 1 + a 1 r = 4 &#8230; 1 a 3 + a 4 = 16 &#8658; a 1 r 2 + a 1 r 3 = 16 &#8230; 2 1 r 2 = 1 4 &#8658; r 2 = 4 &#160; &#8658; r = - 2 &#160; &#160; a 1 &#60; 0 &#8721; i = 1 a a i = a 1 r 9 - 1 r - 1 = - 4 - 2 9 - 1 - 2 - 1 = 4 3 - 513 = 4 &#955; &#955; = - 171 .

Let a 1 , a 2 , a 3 , … , be a G . P . such that a 1 < 0 , a 1 + a 2 = 4 and a 3 + a 4 = 16 . If…

Solution

Let a 1 , a 2 , a 3 , &#8230; , be a G . P . such that a 1 &#60; 0 , a 1 + a 2 = 4 and a 3 + a 4 = 16 . If…

Solution

Let a 1 , a 2 , a 3 , … , be a G . P . such that a 1 < 0 , a 1 + a 2 = 4 and a 3 + a 4 = 16 . If…