Y=cos2x
y' = (cos2x)' * (2x)' = -sin2x*2=-2sin2x
10,5 - 5х = 0
10,5 - 0 = 5х
10,5 = 5х
х = 10,5 : 5
<u>х = 2,1
</u>10,5 - 5 × 2,1 = 0<u>
</u>
...............................на фото.............................
3) f(x) = (6x -1)⁻⁵
f'(x) = -5(6x -1)⁻⁶ * (6x -1)' = -30/(6x -1)⁶
f'(x₀) = f'(1/3) = -30/(6*1/3 -1)⁶ = -30
4) f(x) = √(3x² +4)
f'(x) = 1/2√(3x² +4) * (3x² +4)' = 6x/2√(3x² +4) = 3x/√(3x² +4)
5) f(x) = x⁵ - 3 1/3 x³ +5x
f'(x) = 5x⁴-10x² +5
f'(x₀) = f'(-1) = 5 -10 +5 = 0
0,2х-0,2-2+0,8х-2,3
1х-4,5
________
х=0,3; 0,3-4,5= -4,2