f(x)=√x-1  g(x)=√3-xF=f+g={√ x-1+√3-x}D(F)={√ x-1+√3-x}⇔{ x≥1, x≤3}⇒ D(F)=[1;3]բ)F=f-g=√x-1-√3-xD(F)={√ x-1+√3-x}⇔{ x≥1, x≤3}⇒ D(F)=[1;3]գ)F=f*g=√ x-1*√3-xD(F)={√ x-1*√3-x}⇔{ x≥1, x<3}⇒ D(F)=[1;3]դ)F=f/g=√ x-1/√3-xD(F)={x-1≥0, 3-x≥0, 3-x≠0⇔{ x≥1, x<3}⇒D(F)=[1;3]215f(x)=1+x² g(x)=1/1-xF=fºgF=1+(1/1-x)²=(1-x)²+1/(1-x)²=1-2x+x²+1/(1-x)²=x²-2x+2/(1-x)²