Răspuns:
Explicație pas cu pas:
2a)
1/
(x+1)+1/(x-1)=(x-1+x+1)/(x²-1)=2x/(x²-1)
b)E(x)=[1/(x²-1)+2x/(x²-1)]·(x+1)/(2x+1)=(2x+1)/(x-1)(x+1)·(x+1)/(2x+1)=1/(x-1)
R\±1
4
a)
AB=15 cm AM=9cm MB=6 cm
BC=8 cm ⇒ in Δ dreptunghic MBC CM=ipotenuza=10 cm
b)sin ∡AMC=cos∡CMB
cos∡CMB=MB/BC=6/8=0,75
