Răspuns:
1. sinB= AC/BC
0.8 = 12/BC => BC = 12 : 0.8 = 15cm
cosB=AB/BC
AB²= BC²-AC²=15²-12²= 225-144= 81
AB= /81 = 9cm
=> cosB=9/15= 3/5
tgC= AB/AC = 9/12 = 3/4
2. a) F
b) F
c) A
d) F
3. aici nu se vede cu cat este AB deci nu se pot afla pct
4. sin30⁰+cos60⁰=1/2 + 1/2 = 2/2 = 1
=> a) -> 2.
cos30⁰ +tg60⁰ = radical 3 / 2 + radical 3 (multiplicam cu 2)
r3/2 + 2r3/2 = 3r3/2
=> b) -> 4
sin45⁰+sin60⁰= r2/2 + r3/2
=> c) -> 3
