tentukan jumlah 10 suku pertama barisan dengan rumus un=9n-2

un = 9n - 2
u1 = 9.1 - 2 =7
u2 = 9.2 - 2 =16
u3 = 9.3 -2 =25
u4 = 9.4 - 2=34
u5 = 9.5 - 2=43
u6 = 9.6 - 2=52
u7 = 9.7 - 2=61
u8 = 9.8 - 2=70
u9 = 9.9 - 2=79
u10 = 9.10 - 2=88
jadi, jumlah keseluruhan=475
maaf kalo salah

Rumus Un=9n-2

u1=9.1-2
=9-2
=7

u2=9.2-2
=18-2
=16

u3=9.3-2
=27-2
=25

u4=9.4-2
=36-2
=34

u5=9.5-2
=45-2
=43

u6=9.6-2
=54-2
=52

u7=9.7-2
=63-2
=41

u8=9.8-2
=72-2
=70

u9=9.9-2
=81-2
=79

u10=9.10-2
=90-2
=88

jadi, 10 suku pertama adalah 7, 16, 25, 34, 43, 52, 41, 70, 79, 88