1. а)3 б)8-2V15
2. а)-4+Vа б)V21/7
3. а) хз б) V17+V5/3
4.
5. a)|-3,6| = 3,6 б)m^8 в)а^5
Y=f(a)+<span>f′</span>(a)⋅(x−a<span>)
Вычисление производной :
</span><span><span>f′</span>(x)=<span><span>(<span>−<span>x^2</span>+6⋅x+8</span>)</span>′</span>=</span><span>=<span><span>(<span>−<span>x^2</span>+6⋅x</span>)</span>′</span>=</span><span>=<span><span>(<span>−<span>x^2</span></span>)</span>′</span>+<span><span>(<span>6⋅x</span>)</span>′</span>=</span><span>=−<span><span>(<span>x^2</span>)</span>′</span>+6=</span><span>=−2⋅x+6
</span>Подставим числа <span>a=−2;f(a)=−8;<span>f′</span>(a)=10</span><span> в формулу</span>
<span>y=−8+10⋅(x+2)=10x+12
ответ : y=10x+12</span>
1)sin2xsin3x+cos5x=0
1/2(cos(2x-3x)-cos(2x+3x))+cos5x=0
1/2cosx-1/2cos5x+cos5x=0
1/2cosx+1/2cos5x=0
cosx+cos5x=0
2cos3xcos2x=0
cos3x=0 cos2x=0
3x=π/2+πn 2x=π/2+πk
x=π/6+πn/3 n∈Z x=π/4+πk/2 k∈Z
2)cosx-cos3xcos2x=0
cosx-1/2(cos(3x-2x)+cos(3x+2x))=0
cosx-1/2cosx-1/2cos5x=0
1/2cosx-1/2cos5x=0
cosx-cos5x=0
2sin3xsin2x=0
sin3x=0 sin2x=0
3x=πn 2x=πk
x=πn/3 n∈Z x=πk/2 k∈Z
3)sin2xcos5x+sin3x=0
1/2(sin(-3x)+sin7x)+sin3x=0
-1/2sin3x+1/2sin7x+sin3x=0
1/2sin3x+1/2sin7x=0
sin3x+sin7x=0
2sin5xcos(-2x)=0
2sin5xcos2x=0
sin5x=0 cos2x=0
5x=πn 2x=π/2+πk
x=πn/5 n∈Z x=π/4+πk/2 k∈Z
4)sin7x-cos3xsin4x=0
sin7x-1/2(sin(-x)+sin7x)=0
sin7x+1/2sinx-1/2sin7x=0
1/2sin7x+1/2sinx=0
sin7x+sinx=0
2sin4xcos3x=0
sin4x=0 cos3x=0
4x=πn 3x=π/2+πk
x=πn/4 n∈Z x=π/6+πk/3 k∈Z
Начальная цена пальто = А грн.
после 1-го снижения цена стала 0,85А гр
после 2-го снижения цена стала:
0,85А - 100%
х - 90% х = 0,85А*90/100 = 0,765А(грн)
0,765А грн = 918 грн
А =918:0,765= 1200(грн.)