Question

find the sum of series 1+(1+2)+(1+2+3+4)+........+(1+2+3+4+.....+20)​

Answer 1

Step-by-step explanation:

$\huge\underline\mathfrak\color{red} Answer$

1+(1+2)+(1+2+3+4)

--> 3+(1+2+3+4)

--> 14

hope it helps you;!