Răspunsuri

2014-08-11T11:21:14+03:00
1) sin 60= √3/2

tg30= 1/√3=  √3/3

( √3/2 +√3/3) ^ -2 * √625/144

(3√3+2√3)/6 ^-2 *25/12=

=( 5√3/6) ^ -2 * 25/12=

= 1/(5√3/6)² * 25/12=

= 36/75 *25/12=

=3/3=1

2)V=d/t

d=V*t

t=d/V

t=6h

25% din V=25/100 *V= 1/4*V=  V/4  se reduce

V-V/4=  (4V-V)/4=  3V/4  -restul

V.........6h
3V/4.....x

x=  V * 6/3V/4

x= V*6 * 4/3V

x= 2*4

x=8h
de unde l.ai luat pe 1? 1/(5√3/6)² * 25/12=