bài 1 ; bỏ dấu ngoặc rồi thực hiện phép tính
a, -5-\((\)-3\()\)\(+\)\((\)-4\()\)-\((\)2-4\(+\)3\()\)
b, 2-\((\)\(+\)4\()\)-\((\)-3\()\)\(+\)\((\)-5\(+\)7\()\)
c,-5-\((\)-5\()\)-\((\)-4\(+\)8\()\)
bài 2 ,rút gọn;
a, \((\)-x\(+\)4\()\).\((\)x2\(+\)4x\(+\)16\()\)
b, -3x2\((\)-5x\(+\)4y\()\)\(+\)5xy.\((\)-3x\(+\)2\()\)
c,...
Đọc tiếp
bài 1 ; bỏ dấu ngoặc rồi thực hiện phép tính
a, -5-\((\)-3\()\)\(+\)\((\)-4\()\)-\((\)2-4\(+\)3\()\)
b, 2-\((\)\(+\)4\()\)-\((\)-3\()\)\(+\)\((\)-5\(+\)7\()\)
c,-5-\((\)-5\()\)-\((\)-4\(+\)8\()\)
bài 2 ,rút gọn;
a, \((\)-x\(+\)4\()\).\((\)x2\(+\)4x\(+\)16\()\)
b, -3x2\((\)-5x\(+\)4y\()\)\(+\)5xy.\((\)-3x\(+\)2\()\)
c, 4xy.\((\)3x2-5\()\)-3y\((\)4x3-5yx\()\)
a/\(-5-\left(-3\right)+\left(-4\right)-\left(2-4+3\right)\)
= -5+3 -4- 1
= -7
b/\(2-\left(+4\right)-\left(-3\right)+\left(-5+7\right)\)
= 2 -4 +3 +2
= 3
c/ \(-5-\left(-5\right)-\left(-4+8\right)\)
= -5 +5 -4
= -4
\(\left(-x+4\right)\left(x^2+4x+16\right)\)
= -x3- 4x2-16x+4x2+16x+64
= -x3+64 =(-x+4).( -x2-4x+42)