a ) \(\left(x+3\right).\left(x^2-3x+9\right)-x.\left(x-2\right)\left(x+2\right)\)
\(=x^3+9-x.\left(x^2-4\right)\)
\(=x^3+9-x^3+4x\)
\(=9+4x\)
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Các câu hỏi tương tự
Tinh
a) \(\left(x+y\right)^3+\left(y-x\right)^3\)
b) \(\left(x+3\right).\left(x^2-3x+9\right)-x.\left(x-2\right).\left(x+2\right)\)
Tính
\(\left(x+y\right)^3-x.\left(x+3y\right)^2+y.\left(y-3x\right)^2\)
Tim x
a) \(\left(x+3\right)^3-x.\left(3x+1\right)^2+\left(2x+1\right).\left(4x^2-2x+1-3x^2\right)=54\)
b) \(\left(x-3\right)^3-\left(x-3\right).\left(x^2+3x+9\right)+6.\left(x+1\right)^2+3x^2=-33\)
rút gọn
a)\(\left(7x-8\right).\left(7x+8\right)-10.\left(2x+3\right)^2+5x.\left(3x-2\right)^24x.\left(x-5\right)^2\)
b) \(\left(3x+7\right)^3-\left(5x-y\right).\left(25x^2+5xy+y^2\right)+\left(x+2y\right)^3\)
Rút gọn
a) \(x.\left(x+4\right).\left(x-4\right)-\left(x^2+1\right).\left(x-1\right)\)
b) \(\left(y-3\right).\left(y+3\right).\left(y^2+9\right)-\left(y^2+2\right).\left(y^2-2\right)\)
chứng tỏ gia strij của biểu thức ko phụ thuộc vào các biến
\(4\left(x-6\right)-x^2\left(3x+1\right)+x\left(5x-4\right)+3x^2\left(x-1\right)\)
b) \(xy\left(3x^2-6xy\right)-3\left(x^3y-2x^2y^2-1\right)\)
B1 ( kết quả thôi ko cần lời giải)a) left(4x-3right)left(3x+2right)-left(6x+1right)left(2x-5right)+1b) left(3x+4right)^2+left(4x-1right)^2+left(2+5xright)left(2-5xright)c) left(2x+1right)left(4x^2-2x+1right)+left(2-3xright)left(4+6x+9x^2right)-9B2 tìm x(kết quả)a) 3xleft(x-4right)-xleft(5+3xright)-34b) left(3x+1right)^2+left(5x-2right)^234left(x+2right)left(x-2right)c) x^3+3x^2+3x+280
Đọc tiếp
B1 ( kết quả thôi ko cần lời giải)
a) \(\left(4x-3\right)\left(3x+2\right)-\left(6x+1\right)\left(2x-5\right)+1\)
b) \(\left(3x+4\right)^2+\left(4x-1\right)^2+\left(2+5x\right)\left(2-5x\right)\)
c) \(\left(2x+1\right)\left(4x^2-2x+1\right)+\left(2-3x\right)\left(4+6x+9x^2\right)-9\)
B2 tìm x(kết quả)
a) \(3x\left(x-4\right)-x\left(5+3x\right)=-34\)
b) \(\left(3x+1\right)^2+\left(5x-2\right)^2=34\left(x+2\right)\left(x-2\right)\)
c) \(x^3+3x^2+3x+28=0\)
Tìm x: \(\left(3x-1\right)^3-2\left(2x-3\right)^2-3\left(x-2\right)\left(3-x\right)=\left(1+3x\right)^3-2\left(1+3x\right)^2\)
Tìm x : \(\left(x-1\right)^3-2\left(x-2\right)^2=\left(2+3x\right)^3-3\left(x+1\right)^2-\left(x-1\right)\left(x-2\right)\)