\(=\dfrac{2a\left(a-b\right)}{a\left(c+d\right)-b\left(c+d\right)}=\dfrac{2a\left(a-b\right)}{\left(a-b\right)\left(c+d\right)}=\dfrac{2a}{c+d}\)
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:
1 \(\dfrac{x^2-18x-19}{x^2-1}\)
2 \(\dfrac{x\left(4x^2-8x+4\right)}{2x^3-2x^2}\)
rut gon bieu thuc sau : P=2(x+y)(x-y)-(x-y)^2+(x+y)^2-4y^2
rut gon bieu thuc sau P=\(2\left(x+y\right)\left(x-y\right)-\left(x-y\right)^2+\left(x+y\right)^2-4y^2\)
Rut gon bieu thuc
A=(x+1)\(\left(x^2+1\right)\left(x^4+1\right)...\left(x^{256}+1\right)+1\)
Rut gon va tinh gia tri bieu thuc
A= (x-4).(x-2)-(x-1).(x-3) tại x= \(1\dfrac{3}{4}\)
rut gon bieu thuc
((x^2+a)(1+a)+a^2x^2+1):((x^2-a)(1-a)+a^2x^2+1)
cm ptrinh treb ko phu thuoc vao x
cho Δabc có BC=5,AC=4,AB=6 và AD là đường phan giác . tinh BD
Rut gon cac bieu thuc sau
b,P=\(\left(3x+1\right)^2-2\left(1+3x\right)\left(3x+5\right)+\left(3x+5\right)^2\)
T=(3+1)\(\left(3^2+1\right)\left(3^4+1\right)\left(3^8+1\right)\)
