X=π/4+πn, n∈Z [5π;13π/2]= [5π; 6,5π]
n=0 x1=π/4+0π=π/4∉ [5π; 6,5π]
n=1 x2=π/4+π=5π/4∉ [5π; 6,5π]
n=2 x3=π/4+2π=9π/4∉ [5π; 6,5π]
n=3 x4=π/4+3π=13π/4∉ [5π; 6,5π]
n=4 x5=π/4+4π=17π/4∉ [5π; 6,5π]
<u>n=5 x6=π/4+5π=21π/4∈[5π; 6,5π]</u>
<u>n=6 x7=π/4+7π=25π/4∈ [5π; 6,5π]
</u>n=7 x8=π/4+8π=33π/4∉ [5π; 6,5π]
Ответ: 21π/4; 25π/4
F(-3) = 2*(-3) -3 = -6-3=-9
F(2-3x) = 2*(2-3x) - 3= 4-6x-3=1-6x
F(x^2 - 4) = 2*(x^2 - 4) -3= 2x^2-8-3=2x^2-11
1-2sin²x+5sinx+2=0
sinx=a
2a²-5a-3=0
D=25+24=49
a1=(5-7)/4=-1/2⇒sinx=-1/2⇒x=(-1)^(n+1)*π/6+πn,n∈z
a2=(5+7)/4=3⇒sinx=3>1 нет решения
8. x²-7x-18=0
D=121
Ответ: -2; 9
9.y=2x+8 и
⇒ 4x+16=6-x ⇒ 5x=-10 ⇒ x=-2 (абсцисса точки С)