Bài 1:
a, (-313) + 176 - 87 + (-76)
= - (313 + 87) + (176 - 76)
= - 400 + 100 = -300
b, 17. (-56) + 17. (-30) + 17. (-4)
= -17. (56+30+4)
= -17. 90 = -1530
c, (-2) + (-5) + (-8) +...+ (-182)
= (-182 -2) : 2 x 61
= -5612
d, 1 - 3 + 5 - 7 + 9 - 11 + ... + 97 - 99
= (1-3) + (5-7) + (9-11) +...+ (97 - 99)
= -2 - 2 - 2 +... - 2
= -2 x 25 = -50
Bài 2:
\(a,3\left(3x-1\right)+2\left(1-5x\right)-4\left(2-3x\right)\\ =9x-3+2-10x-8+12x\\ =\left(9x-10x+12x\right)+\left(2-3-8\right)\\ =11x-9\\ ---\\ b,-3\left(x-1\right)-4\left(4-2x\right)-2\left(x+5\right)\\ =-3x+3-16+8x-2x-10\\ =\left(-3x+8x-2x\right)+\left(3-16-10\right)\\ =3x-23\)
