A3) f(x) = x/(x-1) = 1 + 1/(x-1) =1+(x-1) ^(-1).
A3) =4 =
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f(x) =x/(x -1) = 1 + 1/(x-1) =1 +(x-1)^(-1)
f '(x) =((x)'*(x-1) -(x-1)'*x)/x² = (1*(x-1) -1*x)/(x-1)² = -1/(x-1)².
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f'(x) = -1*(x-1) ^(-2) = -1/(x-1)² ;
f '(0) = -1/(0-1)² = -1/1 = -1.
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A4) =3=
2sin²x +4 -3cos²x = 2sin²x +4 -3(1-sin²x) =5sin²x+1 ***||4sin²x =1 ⇒sin²x =1/4 || ***
=5*1/4+1 =2,25.
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A5) =2=
((7-x)(6-x))/(x+1) ≤ 0;
((x -6)(x-7))/(x+1) ≤ 0;
- + - +
------------------------ - 1 --------------- 6 ---------------- 7 -------------- медотом интервалов ---
x∈(-∞ ;-1) U [6 ;7] .
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A6) =3=.
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A7) =3=
3 -2sinx || sinx= -1; sinx =1 ; 3 -2(-1) =5 ;3 -2*1 =1; 5+1 =6 || .
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A8) =4=
f(x) =2,5*x^4 - 4x³ +7x -5 ;
f ' (x) =(2,5*x^4 - 4x³ +7x -5 )' =(2,5*x^4)' - (4x³)' +(7x)' -( 5)'=
2,5*4x³ - 4*3x² +7 -0 = 10 x³ -12x² +7.
=4=