5.19
б) f(x)=x^2; x0=1 г)x0=-1
y=f(x0) +f'(x0) *(x-x0)
f(1)=1^2=1 f(-1)=(-1)^2=1;
f'(x)=(x^2)'=2x; f'(1)=2*1=2; f'(x)=2x; f'(-1)=2*(-1)=-2
y=1+2*(x-1) y=1-2*(x+1); y=1-2x-2
2x-y=1 2x+1=-1
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5.21
y=x^3-3x^2+x-1; y=f(x)
y=f(x0)+f'(x0) *(x-x0)
б)х0=1 г) х0=-2
f(1)=1-3+1-1=-2 f(-2)=(-2)^3 -3(-2)^2-2-1=-8-12-3=-23
f'(x)=3x^2-6x+1
f'(1)=3*1-6*1+1=-2; f'(-2)=3*(-2)^2-6*(-2)+1=12+12+1=25
y=-2-2(x-1) y=-23+25*(x+2)
2x+y=-2+2 y=-23+25x+50
2x+y=0 25x-y=-27
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