Question

SOS vs ạ mn 

Answer 1

h)\(\dfrac{x+2}{x^2+2x+1}\ge0\)

⇔\(\dfrac{x+2}{\left(x+1\right)^2}\ge0\)

⇔\(\dfrac{x+2}{\left(x+1\right)\left(x+1\right)}\ge\dfrac{0.\left(x+1\right)\left(x+1\right)}{\left(x+1\right)\left(x+1\right)}\)

⇒\(x+2\ge0\)

⇔\(x+2-2\ge0-2\)

⇔\(x\ge-2\)

i)\(\dfrac{x-1}{x-3}>1\)

⇔\(\dfrac{x-1}{x-3}>\dfrac{1.\left(x-3\right)}{1.x-3}\)

⇒\(x-1>x-3\)

⇔\(x-x>-3+1\)

⇔\(0x>-2\)