1
сtg3x-ctgx=0
sin(3x-x)/sin3x*sinx=0
sin2x=0 U sin3x*sinx≠0
2x=πn⇒x=πn/2,n∈z U x≠πk,k∈z U x≠πm/3,m∈z
x=πn/2,n∈z U n≠2m/3,m∈z
3
sin(2x+4x)/cos2xcos4x=sin(5x+x)/cos5xcosx
sin6x/cos2xcos4x-sin6x/cos5xcosx=0
sin6x(cos5xcosx-cos2xcos4x)/cosxcos2xcos4xcos5x=0
cosxcos2xcos4xcos5x≠0
sin6x=0⇒x=πn/6,n∈z
cos5xcosx-cos2xcos4x=0
1/2*cos4x+1/2*cos6x-1/2*cos2x-1/2*cos6x=0
1/2*cos4x-1/2*cos2x=0
-1/2*2sinxsin3x=0
sinx=0⇒x=πk,k∈z
sin3x=0⇒x=πm/3,m∈z
MN=NF=OP=5√3
FO=√(FP²-OP²)=√(100-75)=√25=5
MP=NO=NF+NO=5+5√3=5(√3+1)
1) 5-2(x+3)<=3x+1
-2x-6<=3x-4
-2<=5x
x=>-2/5
Ответ [-0.4;+∞)
2) x<2
-6<4x
x<2
x>-1.5
Ответ: (-1.5;2)
3) -2<=-3x+4
-3x+4<10
x<=2
x>-6
Ответ: (-6;2]
4) а) 2x-3 > 0
2x>3
x>1.5
Ответ: (1,5;+∞)
б) 3-x=>0
2x-1=>0
x<=3
x=>0.5
Ответ: [0.5; 3]
в) 3x-15>0
x^2-7x≠0
x>5
x(x-7)≠0
Ответ: (0;5)∪(5;7)∪(7;+∞)
5. (3x-1)-2(x+1)<=8x+4
x<=1.5
x=>-1/7
Ответ: [-1/7;1.5]
6. |5-2x|=7-4x
(5-2x)^2=(7-4x)^2
25+4x^2-20x=49+16x^2-56x
-12x^2+36x-24=0
6x^2-18x-12=0
x^2-6x-2=0
x12=