Question

Suku ke 25 dari barisan aritmatika 4, 7, 10, 13

Answer 1

U1(a) = 4 ; u2-u1(b) =3; rumus => un=a+(n-1)b ; <=> u25=4+(25-1)3 <=>u25=4+(24)3 <=>u25=4+72 <=>u25=76

Answer 2

penyelesaian :
a = 4
b = 7-4=10-7=13-10=3
Un = a + (n-1) b         
     = 4 + (25-1)3        
     = 4 +   (24).3          
     = 4 + 72
     = 76