Răspuns:
2.
∆ ABC dreptunghic
AB =8cm
AD perpendicular pe BC
BD =2cm
BC=?
∆ ABC dreptunghic. |
AD perpendicular pe BC | => AB = √BD•BC
=> BC = AB •AB / BD
= 8•8/2
= 64/2
BC = 32 cm
4.
sin 30° +cos 60°= 1/2 +1/2
= 2/2
=1
6.
∆ ABC dreptunghic isoscel
AB=AC=4cm
BC=?
=> T.P => AB•AB +AC•AC=BC•BC
=> 4•4+4•4= BC•BC
=>32=BC•BC
=> BC = √32
=> BC = 4√2 cm