Bài 8:
a: \(-64+8\cdot\left(77-19\right)\)
\(=8\cdot\left(-8\right)+8\cdot58\)
\(=8\cdot\left(-8+58\right)=8\cdot50=400\)
b: \(128\left(278-302\right)+278\left(302-128\right)\)
\(=128\cdot278-128\cdot302+278\cdot302-278\cdot128\)
\(=-128\cdot302+278\cdot302\)
\(=302\cdot\left(278-128\right)=302\cdot150=45300\)
c: \(\left(-8\right)\cdot7\cdot\left(-3\right)\cdot\left(-5\right)\)
\(=-3\cdot7\cdot5\cdot8\)
\(=-21\cdot40=-840\)
d: \(2\cdot\left(-7\right)^2+3\cdot\left(-4\right)^3-60\)
\(=2\cdot49+3\cdot\left(-64\right)-60\)
=98-192-60
=-154
Bài 9:
a: \(\left(-2\right)\cdot\left(-6\right)^2+3\cdot\left(-2\right)^3-62\)
\(=-2\cdot36+3\cdot\left(-8\right)-62\)
\(=-72-62-24\)
=-158
b: \(\left(-6\right)\cdot4\cdot\left(-7\right)\cdot\left(-25\right)\)
\(=-6\cdot7\cdot4\cdot25\)
\(=-42\cdot100=-4200\)
c: \(\left(-85\right)+\left(-105\right)+62\)
=-85-105+62
=-190+62
=-128
d: \(24\cdot\left(-15\right)+\left(-15\right)\cdot75+15\)
\(=\left(-15\right)\cdot\left(24+75\right)+15\)
\(=-15\cdot99+15=-15\left(99-1\right)=-15\cdot98=-1470\)
Bài 10:
a: \(\left(-2\right)^3\cdot82+36\cdot\left(-2\right)^3+7\cdot\left(-2\right)^3\)
\(=\left(-2\right)^3\cdot\left(82+36+7\right)\)
\(=-8\cdot125=-1000\)
b: \(\left(-11\right)\cdot5\cdot\left(-12\right)\cdot\left(-20\right)\)
\(=-11\cdot12\cdot5\cdot20\)
\(=-132\cdot100=-13200\)
c: \(\left(-35\right)+84+\left(-165\right)+116\)
=(-35-165)+(84+116)
=200+(-200)
=0
d: \(26\cdot\left(-38\right)+26\cdot\left(-46\right)-26\cdot16\)
\(=-26\cdot\left(38+46+16\right)\)
\(=-26\cdot100=-2600\)
