Question

PLEASEEE HELPP
If a₁ = 10 and an
10 and an = -4an-1 then find the value of a4.

Answer 1

Given the recursive relation:

`a_(n)=-4a_(n-1)`

`a_(2)=-4a_(2-1) = -4a_(1) = - 4(10) = -40 \\ a_(3)=-4a_(3-1) = -4a_(2) = - 4( -4 0) = 160 \\ a_(4)=-4a_(4-1) = -4a_(3) = - 4(160) = -640`