Question

U1 = 2x+1, u2 = 5x-3 u3 = 20x tentukan jumpah deret u1+u2,...+u10

rumus juga gan, pening

Answer 1

U1=2x+1= 2 x 1 +1 = 3
u2=5x-3 = 5 x 2 -3 = 7
beda= 4
un = u1+(n-1)b
= 3+(n-1)4
= 3+4n-4= 4n-1
u10= 4 x 10 -1
= 39
S10= 1/2 x 10(u1+u10)
=1/2 x 10 (3+39)
=210