HEY, HI, PLS GIVE ME THE VALUE OF 1X1!+2X2!+3X3!+....+NXN!=

We can write1*1! As (2-1)*1! . similarly we can write 2*2! As (3-2)*2!.Equation will become as under(2-1)*1!+(3-1)*2!.....(n+1-1)*n!2*1!-1!+3*2!-2!+4*3!-3!....(n+1)*n!-n!2*1! Will be canceled by 2!Similarly 3*2! Will be cancelled by 3!At last result will be=(n+1)*n!-1!

Approved