Question

R= 1²+2²+3²+.....+50²

Answer 1

\(R=1^2+2^2+3^2+...+50^2\)(50 số)

\(R=\left(1+2+3+...+50\right)\left(50số\right)\)

\(R=\left[\left(1+50\right)+\left(2+49\right)+\left(3+48\right)+...\right]^2\left(25cặp\right)\)

\(R=\left(51+51+51+...+51\right)^2\left(25số51\right)\)

\(R=\left(51.25\right)^2\)

\(R=1275^2\)

 

Answer 2

R= 1^2+....+50^2

R=( 1+2+3+...+50)^2

R=\(\left[50.\left(50+1\right)\right]^2\):2

R= (2550:2)^2

R=1275^2

R=1

Answer 3

R = 1^2 + ... + 50^2

R = ( 1 + 2 + 3 + ... +50 )^2

R = [ 50 . (50 + 1 ) ]^2 : 2

R = ( 2550 : 2 )^2

R = 1257^2