Seutas tali dibagi menjadi 6 bagian dengan ukuran panjang membentuk deret geometri, jika bagian yang paling pendek 3 meter dan bagian terpanjang 96 meter, tentukan ukuran panjang tali tersebut
izharulhaq78
![U_n=ar^{n-1}\\U_6=3\times r^{6-1}\\96=3\times r^{5}\\32=r^{5}\\\sqrt[5]{32}=r\\2=r\\\\S_n=\frac{a(r^n-1)}{r-1}\\S_6=\frac{3(2^6-1)}{2-1}\\S_6=\frac{3(64-1)}{1}\\S_6=3(63)\\\boxed{S_6=189m}](https://tex.z-dn.net/?f=U_n%3Dar%5E%7Bn-1%7D%5C%5CU_6%3D3%5Ctimes+r%5E%7B6-1%7D%5C%5C96%3D3%5Ctimes+r%5E%7B5%7D%5C%5C32%3Dr%5E%7B5%7D%5C%5C%5Csqrt%5B5%5D%7B32%7D%3Dr%5C%5C2%3Dr%5C%5C%5C%5CS_n%3D%5Cfrac%7Ba%28r%5En-1%29%7D%7Br-1%7D%5C%5CS_6%3D%5Cfrac%7B3%282%5E6-1%29%7D%7B2-1%7D%5C%5CS_6%3D%5Cfrac%7B3%2864-1%29%7D%7B1%7D%5C%5CS_6%3D3%2863%29%5C%5C%5Cboxed%7BS_6%3D189m%7D "U_n=ar^{n-1}\\U_6=3\times r^{6-1}\\96=3\times r^{5}\\32=r^{5}\\\sqrt[5]{32}=r\\2=r\\\\S_n=\frac{a(r^n-1)}{r-1}\\S_6=\frac{3(2^6-1)}{2-1}\\S_6=\frac{3(64-1)}{1}\\S_6=3(63)\\\boxed{S_6=189m}")
2 votes
Thanks 2
dewanda94
jelas sekali :D terima kasih atas bantuannya Izharulhaq (y)
Fanchidielz
maaf, itu 32 dari mana ya? trims
Brillian07
3 + 6 + 12 + 24 + 48 + 96 = 189 meter
2 votes
Thanks 4
dewanda94
Brillian terima kasih sudah mau membantu :D