Question

1+2+3+4+5+6_____+∞=????​

Answer 1

Answer:

21

Step-by-step explanation:

6+4=10

5+2+3=10

10+10=20

20+1=21

Answer 2

Answer:

We know that

(1+x)^-2=1–2x+3x^2–4x^3+…upto infinity

Now putting x=1 equation becomes

(1+1)^-2=1–2+3–4…upto infinity

2^-2=1–2+3–4….

Or1/2^2=1–2+3–4…..

1–2+3–4….=1/4