pada deret geometri, suku ke -2 = 9 dan suku ke -6 = 144, nilai suku ke -4 adalah... a. 16 b. 18 c. 32 d. 36 tolong sertakan cara nya ya..

U6/U2 = ar^5/ar = 144/9
r⁴ = 144/9
r = √12/3
ar = 9
a(√12/3) = 9
a²(12/3) = 9²
a² = 81 × 3/12
a² = 243/12
a = √243/12
U4 = ar³ = (√243/12)(√12/3)³
= (√243/12)(12/3)(√12/3)
= (12/3)(√243/12×12/3)
= (12/3)(√243/3)
= (12/3)(√81)
= (12/3)(9)
= 36