\(\left(\sqrt{2x}-y\right)^2=\left(\sqrt{2x}\right)^2-2.\sqrt{2x}.y+y^2\\ =2x-2y.\sqrt{2x}+y^2\)
\(\left(\sqrt{2}x-y\right)^2=2x^2-2\sqrt{2}xy+y^2\)
\(\left(\sqrt{2x}-y\right)^2=\left(\sqrt{2x}\right)^2-2.\sqrt{2x}.y+y^2\\ =2x-2y.\sqrt{2x}+y^2\)
\(\left(\sqrt{2}x-y\right)^2=2x^2-2\sqrt{2}xy+y^2\)
Tính
a)(2x^2+y).(2x^2-y)-4x^2+y^2
b)(2x^2+y)^2-(2x^2-y^2)
c)(2x+1)(2x-1)-4x^2
d)(2x^3y+y)^2-(y-2x^3y)^2
tính
a)(2x+1).(2x-1)-4x^2
b)(2x^2+y)(2x^2-y)-4x^2+y^2
c)(2x^2+y)^2-(2x^2-Y)^2
CM tổng sau :
\(\frac{2x+y}{2x^2-xy}+\frac{8y}{y^2-4x^2}+\frac{2x-y}{2x^2+xy}=\frac{2.\left(2x-y\right)}{x.\left(2x+y\right)}.\)
phân tích đa thức thành nhân tửa) B=5x(x-4y)-4y(y-5x)
b)M=(2x+y)^2-(2x+y)(2x-y)=y(x-y)
c)N=(a-3b)^2-(a+3b)^2-(a-1)(b-2)
d)P=(2x-5)(2x+5)-(2x+1)^2
e)Q=(y-3)(y+3)(y^2+9)-(y^2+2)(y^2-2)
2x+y/2x mũ 2-xy+8y/y mũ 2-4x mũ 2+2x-y/2x mũ 2+xy
Rút gọn:
a)2x.(3x-1)-(x-3).(6x+2)
b)(2x-3)2-(1+2x).(2x-1)+3.(2x-3)
c)(x+y-1)2-2.(x+y-1).(x+y)+(x+y)2
Tìm x nguyên sao cho y nguyên
a, y=2/2x-3
b, y=2x-1/2x-3
c, y=2x^2-1/2x-3
d, y=2x-3/2x^2-1
e, y=2x^2-3x-4/4-x
AI NHANH MIK TICK CHO
Tinh A=2/3. X2Y(2X2-Y/3)-2X2(2X2+1)+(2X2-Y/3)(1-Y/3)(2X2-1)