Question

Find the sum of series 3+5+7+9+.............50 terms​

Answer 1

Answer: 2600

Explanation:

`u_1=3\\u_2=5=3+2=3+2*(2-1)\\u_3=7=5+2=3+2*2=3+2*(3-1)\\u_4=9=3+2*3=3+2*(4-1)\\...\\u_n=3+2*(n-1)\\\\u_(50)=3+2*49=101\\\\\displaystyle \sum_(i=1)^(50)(3+2*i)=(3+101)/(2) *50=2600\\`