Tentukan 5 suku pertama dan pola bilangan Un = 1/2 n2 + 1/2

Un = 1/2n² + 1/2
U1 = 1/2(1)² + 1/2 = 2/2 = 1
U2 = 1/2(2)² + 1/2 = 5/2 = 2 1/2
U3 = 1/2(3)² + 1/2 = 10/2 = 5
U4 = 1/2(4)² + 1/2 = 17/2 = 8 1/2
U5 = 1/2(5)² + 1/2 = 26/2 = 13

5 suku pertama yaitu 1, 2 1/2, 5, 8 1/2, 13, ....

u1 = 1/2x1²+1/2
u1= 1

u2= 1/2x2²+1/2
u2= 4/2+1/2
u2= 5/2

u3= 1/2x3²+1/2
u3= 9/2+1/2
u3=10/2= 5

u4= 1/2x4²+1/2
u4= 16/2+1/2
u4= 17/2

u5= 1/2 x 5²+1/2
u5= 25/2+1/2
u5= 26/2= 13