<span>^ -степень
S = [4;6] ∫ 2хdx = x^2 |</span>[4;6] = 6^2 -4^2= 36-16 =20
Sin2x Представляем как:
sin2x=2sinxcosx+1-1=2sinxcosx+sin^2x+cos^2x-1=(sinx+cosx)^2-1
(sinx+cosx)^2-1-5(sinx+cosx)+5=0
Замена sinx+cosx=a
a^2-1-5a+5=0
a^2-5a+4=0
a1=4 Исключаем (т.к sinx+cosx<2)
a2=1
sinx+cosx=1
x=П/k ,kZ
х=П/2+Пк ,kZ
7x+9-9=4x+3-9
7x-4x=-6
3x=-6
x=-2
Ответ:x=-2.
X = 1 - 2y
( 1 - 2y)y + 1 = 0 *
*
y - 2y^2 + 1 = 0
2y^2 - y - 1 = 0
D = 1 + 4*2 = 9
y1 = ( 1 + 3)/4 = 1
y2 = ( 1 - 3)/4 = - 2/4 = - 1/2
x1 = 1 - 2y = 1 - 2*1 = - 1
y1 = 1
x2 = 1 - 2y = 1 - 2*(-1/2) = 2
y2 = - 1/2
Ответ:
( - 1; 1) ; ( 2; - 1/2)
sin(x/2- π/6)+1=0
1 = sin(π/2)
sin(x/2 - π/6) + sin(π/2) = 0
sin(x/2 - π/6) = -sin(π/2)
sin(x/2 - π/6) = sin(-π/2)
x/2 - π/6 = (3x - π)/6
(3x - π)/6 = -π/2
3x - π + 3π = 0
3x +2π = 0
3x = -2π
x = -2π/3
Ответ: -2π/3