f(x)=(x²+4)/(√(3-x)·√(x+1))
Dziedzina funkcji f :
3-x > 0 ∧ x+1 > 0
-x > -3 |:(-1) ∧ x > -1
x < 3 ∧ x > -1
x∈(-1,3)
Df=(-1,3)
[tex]\Large\begin{aligned}&D_f:\sqrt{3-x}\sqrt{x+1}\not=0 \wedge 3-x\geq0 \wedge x+1\geq0\\&D_f:(3-x)(x+1)\not=0 \wedge x\leq 3 \wedge x\geq-1\\&D_f:x\not =3 \wedge x\not =-1 \wedge x\in\langle-3,1\rangle\\&D_f:x\in(-3,1)\end[/tex]
