D=b²-4ac=9-4×1×15=9-60= -51
Нет корней, так как D<0.
a) P_{4} = 4! =1·2·3·4 = 24; б) = 1/40320; b)[tex]C^2_27 = \frac{27!}{2!(27! - 2!)} = 351;
C^2_26 ={26!}{2!(26! - 2!)} =50; 351 - 50 =301;
г) [tex]A^3_10 = \frac{10!}{(10 - 3)!} = 720; [tex]C^3_10 = \frac{10!}{3!(10-3)1} = 120; 720÷120 = ;6
15*-0,9*4/3+18*4/3-6
А дальше photomath в помощь
(log₂32+lne-lg100=log₂2⁵+1-lg10²=5+1-2=4.
(log₂(√5-1)+log₂(√5+1))*log₃49/log₃7=log₂((√5)²-1²)*log₃7²/log₃7=
(log₂4)*2=2*log₂2²=2*2=4.