Bài 4: Cộng hai số nguyên cùng dấu

\(a.\left(-3\right).\left(-2\right).\left(-5\right).4=6.\left(-5\right).4=\left(-30\right).4=-120\)

\(\left(-3\right)\cdot\left(-2\right)\cdot\left(-5\right)\cdot4=6\cdot\left(-5\right)\cdot4=\left(-30\right)\cdot4=-120\)

\(\left(-3\right)\cdot\left(-2\right)\cdot\left(-5\right)\cdot4=6\cdot\left(-20\right)=-120\)

=-596-404+3000+197

=2197

\(a/ (- 25).(- 125).(- 4). (- 8)=[(-25).(-4)].[(-125).(-8)] =100.1000=100000\)

a/(−25).(−125).(−4).(−8)

= [(−25).(−4)].[(−125).(−8)]

= 100.1000

=100000

b/ (-50) . (-80) . (-2) . (-9)

= [(-50) . (-20)] . [ (-80) . (-9) ]

=         100        .       720

=                 72000

-4

\(\left(-17\right)-\left(-13\right)=-17+13=-4\)

= (- 4)

-270

-270

-270

\(-360-360=-720\)

-720

-720

\(x=188:-2\)

\(x=-94\)

 ( - 2 ) . x = 188

           x = 188 : - 2

            x = - 94

b: =-(315+15)=-330

-330

g: =465+58-465-38=20

e)

= [-299+(-201)]+(-300)

=-500+(-300)

=-800

e) (-299) + (-300) + (-201)

= -(299 + 201 + 300)

= -800

g) 465 + 58 + (-465) + (-38)

= [ 465 + (-465)] + [(-38) + 58]

= 0 + 20 = 20

= -(299 + 300 + 201)

= -800

-800

-800 nhé