\(\frac{x^4-y^4}{y^3-x^3}=\frac{\left(x^2\right)^2-\left(y^2\right)^2}{\left(y-x\right)\left(y^2+xy+x^2\right)}=-\frac{\left(x^2-y^2\right)\left(x^2+y^2\right)}{\left(x-y\right)\left(x^2+xy+y^2\right)}=-\frac{\left(x-y\right)\left(x+y\right)\left(x^2+y^2\right)}{\left(x-y\right)\left(x^2+xy+y^2\right)}\)
\(=-\frac{\left(x+y\right)\left(x^2+y^2\right)}{x^2+xy+y^2}\)
RUT GON PHAN THUC
\(\frac{y^2-x^2}{x^3-3x^2y+3xy^2-y^3}\)
Rut gon phan thuc
a, 3x(1-x)\2(x-1)
b, 3(x-y)(x-z)^2\6(x-y)(x-z)
c, x^2-16\4x-x^2 (x#0,x#4)
B1: rut gon bieu thuc
a, (x+y)^2-4(x-y)^2
b, 2(x-y)(x+y)+(x+y)^2+(x-y)^2
B2: tim X
a, (2X-1)^2-4(X+2)^2=9
b, 3(X-1)^2-3X(X-5)=21
B3: Cho bieu thuc
M=(x+3)^3-(x-1)^3+12x(x-1)
a, Rut gon bieu thuc tren
b, Tinh gia tri M tai x=-2/3
c, Tim x de M=16
rut gon bieu thuc [(x^3+y^3)-2(x^2-y^2)+3(x+y)^2]:(x+y)
cho x/a=y/b=z/c .hay rut gon phan thuc P=(x^2+y^2+z^2)/(ax+by+cz)^2
bai 1
a = (3x / 2x + 4 ) + (x +3 /x ^ 2 - 4 )
a . tim x de gia tri phan thuc a duoc xac dinh
b. rut gon a
c. tinh gia trin cua a khi x bang -3
d . tim gia tri cua x de phan thuc co gia tri bang 2
rut gon phan thuc A=(x^3-6x+7)/(x^3+5x^2-2x-24)
rut gon bieu thuc
B= \(\frac{x^3-y^3-z^3-3xyz}{\left(x+y\right)^2+\left(y-z\right)^2+\left(x+z\right)^2}\)
rut gon bieu thuc
p=(x^2+2xy)^2+2(x^2+2xy)y^2+y^4
