Question

bài 1 câu d,e,F ạ

Answer 1

1:

a: Khi x=4 thì \(B=\dfrac{4-3}{2\cdot4-4^2}=\dfrac{-1}{8}\)

b: \(A=\dfrac{4x^2+4+4x+x^2-\left(4-4x+x^2\right)}{\left(2-x\right)\left(2+x\right)}\)

\(=\dfrac{5x^2+4x+4-4+4x-x^2}{\left(2-x\right)\left(2+x\right)}=\dfrac{4x^2+8x}{\left(2-x\right)\left(2+x\right)}=-\dfrac{4x}{x-2}\)

c: P=A:B

=(-4x)/(x-2):(x-3)/(-x(x-2))

\(=\dfrac{4x}{x-2}\cdot\dfrac{x\left(x-2\right)}{x-3}=\dfrac{4x^2}{x-3}\)

P<0

=>x-3<0

=>x<3

e: A nguyên

=>4x chia hết cho x-2

=>4x-8+8 chia hết cho x-2

=>\(x-2\in\left\{1;-1;2;-2;4;-4;8;-8\right\}\)

=>\(x\in\left\{3;1;4;0;6;-6;10\right\}\)

g: Q=4:P

=(x-3)/(x^2)

Q-1=(-x^2+x-3)/x^2<0

=>Q<1