Question

9×{8+7×[6+5×(4+3×(2+1))]}:(1+2+3+.....+9)
va rog sa îl faci desfasurat

Answer 1

=9x{8+7x[6+5x(4+3x3)]}:(1+2+3+........+9)
= 9x{8+7x[6+5x(4+9)]}:(1+2+3+........+9)
= 9x[8+7x(6+5x13)]:(1+2+3+........+9)
=9x[8+7x(6+45)]:(1+2+3+........+9)
=9x(8+7x51):(1+2+3+........+9) 
=9x(8+357):(1+2+3+........+9)
=(9x365):(1+2+3+........+9)
=3285:45
=73

S= 1+2+3+............+9
S= [n(n+1)]:2
S= [9(9+1)]:2
S=(9x10):2= 90:2= 45