1) функция чётная, т.к f(-x)=f(x)
1)18 х (1/3)^2 = 18/1 x 1/9 = 2
(4x - 3y)^2 - (2x + y)(3x - 5y)
(16x^2 - 24xy + 9y^2) - (6x^2 - 10xy + 3xy - 5y^2)
16x^2 - 24xy +9y^2 - 6x^2 + 10xy - 3xy + 5y^2
10x^2 + 14y^2 - 17xy
10x^2 - 17xy + 14y^2
<u>Ответ: 10x^2 - 17xy + 14y^2</u>
1
[cos(π-b)-3sin(-3π/2+b)]/cos(b-3π)=[-cosb+sin(3π/2-b)]/cos(b-π)=
=[-cosb-cosb)/(-cosb)=-2cosb/(-cosb)=-2
3
24√2cos1035=24√2cos(720+315)=24√2cos315=24√2cos(360-45)=
=24√2cos45=24√2*1/√2=24
6
11sin49/sin311=11sin49/sin(360-49)=11sin49/(-sin49)=-11