Question

Calculați, folosind factorul comun:
a)2009²+2008×2009-4018×2009
b)1957×1959-1958×1957
c)2009×2010+2009×2008-2009×4018
d)2009²+2009×2008-2009×4017
× - ori
Ajutor va rog mult​

Answer 1

Explicație pas cu pas:

a)

$2009 \times (2009 + 2008 - 4018) = 2009 \times (4017 - 4018) = 2009 \times ( - 1) = - 2009$

b)

$1957 \times (1959 - 1958) = 1957 \times 1 = 1957$

c)

$2009 \times (2010 + 2008 - 4017) = 2009 \times (4018 - 4017) = 2009$

d)

$2009 \times (2009 + 2008 - 4017) = 2009 \times (4017 - 4017) = 2009 \times 0 = 0$