tolong di bantu yaa

1. a. 4 suku
    b. a = -8
         b = 5
         U10 = a + 9b
                 = -8 + 9.5
                 = -8 + 45
                 = 37
3. a = 18
    r = 6/18 = 1/3
    U10 = ar⁹
            = 18 . 1/3⁹
            = 3² . 2 . 1/3⁹
           = 2/3⁷
 4. U4 = ar³ = 4
     U7 = ar⁶ = 32
     a. ar³.r³ = 32
           4r³ = 32
              r³ = 8
              r = 2
           ar³ = 4
           a. 2³ = 4
             8a = 4
               a = 1/2
   b. U3 = ar²
             = 1/2 . (2)²
             = 1/2 . 4
             = 2