Basic relations of trigonometric functions with the same angle
Reciprocal relation: quotient relation: square relation:
tanα cotα= 1
sinα cscα= 1
cosαsecα= 1 sinα/cosα= tanα= secα/CSCα
cosα/sinα= cotα= CSCα/secαsin 2α+cos 2α= 1
1+tan2α=sec2α
1+cot2α=csc2α
(Hexagon mnemonic method: the graphic structure is "upper chord cut, Zuo Zheng middle cut,1"; The product of two functions on the diagonal is1; The sum of squares of trigonometric function values of two vertices on the shadow triangle is equal to the square of trigonometric function value of the next vertex; The trigonometric function value of any vertex is equal to the product of the trigonometric function values of two adjacent vertices. " )
Inductive formula (formula: odd variable couple, sign according to quadrant. )
Sine (-α) =-Sine α
cos(-α)=cosα tan(-α)=-tanα
Kurt (-α) =-Kurt α
sin(π/2-α)=cosα
cos(π/2-α)=sinα
tan(π/2-α)=cotα
cot(π/2-α)=tanα
sin(π/2+α)=cosα
cos(π/2+α)=-sinα
tan(π/2+α)=-cotα
cot(π/2+α)=-tanα
Sine (π-α) = Sine α
cos(π-α)=-cosα
tan(π-α)=-tanα
cot(π-α)=-coα
Sine (π+α) =-Sine α
cos(π+α)=-cosα
tan(π+α)=tanα
cot(π+α)=cotα
sin(3π/2-α)=-cosα
cos(3π/2-α)=-sinα
tan(3π/2-α)=cotα
cot(3π/2-α)=tanα
sin(3π/2+α)=-cosα
cos(3π/2+α)=sinα
tan(3π/2+α)=-cotα
cot(3π/2+α)=-tanα
Sine (2π-α)=- Sine α
cos(2π-α)=cosα
tan(2π-α)=-tanα
Kurt (2π-α)=- Kurt α
sin(2kπ+α)=sinα
cos(2kπ+α)=cosα
tan(2kπ+α)=tanα
cot(2kπ+α)=cotα
(where k∈Z)
General formula for sum and difference of formulas of trigonometric functions's two angles
sin(α+β)=sinαcosβ+cosαsinβ
sin(α-β)=sinαcosβ-cosαsinβ
cos(α+β)=cosαcosβ-sinαsinβ
cos(α-β)=cosαcosβ+sinαsinβ
tanα+tanβ
tan(α+β)=———
1-tanα tanβ
tanα-tanβ
tan(α-β)=———
1+tanα tanβ
2 tons (α/2)
sinα=————
1+tan2(α/2)
1-tan2(α/2)
cosα=————
1+tan2(α/2)
2 tons (α/2)
tanα=————
1-tan2(α/2)
Sine, cosine and tangent formulas of half angle; Power reduction formula of trigonometric function
Sine, cosine and tangent formulas of double angles Sine, cosine and tangent formulas of triangle
sin2α=2sinαcosα
cos 2α= cos 2α-sin 2α= 2 cos 2α- 1 = 1-2 sin 2α
2tanα
tan2α=———
1-tan2α
sin3α=3sinα-4sin3α
cos3α=4cos3α-3cosα
3tanα-tan3α
tan3α=————
1-3tan2α
Sum and difference product formula of trigonometric function
α+β α-β
sinα+sinβ= 2 sin——cos——
2 2
α+β α-β
sinα-sinβ= 2cos——sin——
2 2
α+β α-β
cosα+cosβ= 2cos————cos———
2 2
α+β α-β
cosα-cosβ=-2 sin——sin——
2 2 1
sinα cosβ=-[sin(α+β)+sin(α-β)]
2
1
cosα sinβ=-[sin(α+β)-sin(α-β)]
2
1
cosα cosβ=-[cos(α+β)+cos(α-β)]
2
1
sinαsinβ=--[cos(α+β)-cos(α-β)]
2
Convert asinα bcosα into trigonometric function form of angle (formulas of trigonometric functions of auxiliary angle
Set, function
Set simple logic
Any x∈A x∈B is marked as a B.
A B,B A A=B
A b = {x | x ∈ a, and x∈B}
A b = {x | x ∈ a, or x∈B}
Card (A B)= Card (A)+ Card (B)- Card (A B)
(1) proposition
If the original proposition is p, then q
If q is the inverse proposition of p
If p is q, there is no proposition.
If the negative proposition is q, then p.
(2) the relationship between the four propositions
(3)A B, A is a sufficient condition for B to be established.
B A, a is a necessary condition for B.
A B, a is the necessary and sufficient condition of b.
Property Exponent and Logarithm of Function
(1) domain, range, corresponding rules
(2) Monotonicity
For any x 1, x2∈D
If X 1 < X2F (X 1) < F (X2), then F (X) is called increasing function on D.
If x 1 < x2 f(x 1) > f (x2), then f(x) is said to be a decreasing function on d.
(3) Parity
If f (-x) = f(x), f(x) is called an even function for any X in the domain of function F (x).
If f (-x) =-f(x), then f(x) is called odd function.
(4) periodicity
For any x in the definition domain of function f(x), if there is a constant t that makes f(x+t) = f (x), it is said that f(x) is a fractional exponential power of periodic function (1).
The significance of positive fractional exponential power is
The significance of negative fractional exponential power is
(2) The nature and algorithm of logarithm.
loga(MN)=logaM+logaN
logaMn=nlogaM(n∈R)
Exponential function logarithmic function
(1) y = ax (a > 0, a≠ 1) is called exponential function.
(2)x∈R,y>0
Image transfer (0, 1)
When a > 1, x > 0, y > 1; When x 1, y = ax is an increasing function.
0 < a < 1, y = ax is a decreasing function (1), and y = logax (a > 0, a≠ 1) is a logarithmic function.
(2)x>0,y∈R
Image transfer (1, 0)
When a > 1, x > 1, y > 0; 0 1, y = logax is increasing function.
0 < a < 1, y = logax is a decreasing function.
Exponential equation and logarithmic equation
fundamental form
logaf(x)=b f(x)=ab(a>0,a≠ 1)
Same bottom type
logaf(x)= logag(x)f(x)= g(x)> 0(a > 0,a≠ 1)
Substitution type f (ax) = 0 or f (logax) = 0.
Ordered sequence
Basic concept of arithmetic progression of sequence.
The general formula of (1) series an = f (n)
(2) Recursive formula of sequence
(3) The relationship between the general term formula of the sequence and the sum of the first n terms.
an+ 1-an=d
an=a 1+(n- 1)d
A, a and b are equal. 2A = A+B
m+n=k+l am+an=ak+al
Common summation formulas of geometric series
an=a 1qn_ 1
The proportion of A, G and B is equal G2 = AB.
M+n=k+l Oman = Aka
inequality
Basic properties of inequalities Important inequalities
a>b bb,b>c
a>b a+c>b+c
a+b>c a>c-b
a>b,c>d
a>b,c>0 ac>bc
a>b,c0,c>d>0 acb>0 dn>bn(n∈Z,n> 1)
a>b>0 > (n∈Z,n> 1)
(a-b)2≥0
a,b∈R a2+b2≥2ab
|a|-|b|≤|a b|≤|a|+|b|
Basic methods of proving inequality
comparative law
(1) To prove the inequality A > B (or A < B), just prove it.
A-b > 0 (or a-b < 0 =)
(2) if B > 0, to prove that A > B, just prove that,
To prove a < b, prove it.
Synthesis method is a method to deduce the inequality to be proved (from cause to effect) from the known or proved inequality according to the nature of inequality.
Analytical method is to seek the sufficient conditions for the conclusion to be established, and gradually seek the sufficient conditions for the required conditions to be established until the required conditions are known to be correct, which is obviously manifested as "holding the fruit"
plural
Algebraic form triangular form
A+bi =c+ Adi = c and B = D.
(a+bi)+(c+di)=(a+c)+(b+d)i
(a+bi)-(c+di)=(a-c)+(b-d)i
(a+bi)(c+di )=(ac-bd)+(bc+ad)i
a+bi = r(cosθ+isθ)
r 1 =(cosθ 1+isθ 1)? 6? 1r 2(cosθ2+isθ2)
=r 1? 6? 1r 2〔cos(θ 1+θ2)+isin(θ 1+θ2)〕
〔r(cosθ+sinθ)〕n = rn(cosnθ+isinnθ)
k=0, 1,…,n- 1
Analytic geometry
1, straight line
Linear equation of the distance between two points and a fixed fractional point
|AB|=| |
|P 1P2|=
y-y 1=k(x-x 1)
y=kx+b
The positional relationship between two straight lines, including angle and distance.
Or k 1 = k2, and b 1≠b2.
L 1 coincides with l2.
Or k 1 = k2 and b 1 = B2.
L 1 intersects with l2.
Or k 1≠k2
l2⊥l2
Or k 1k2 =- 1L 1 to l2.
The angle between l 1 and l2.
Distance from point to straight line
2. Conic curve
Circular ellipse
The standard equation (x-a) 2+(y-b) 2 = R2.
The center of the circle is (a, b) and the radius is r.
The general equation x2+y2+dx+ey+f = 0.
Where the center of the circle is (),
Radius r
(1) Use the distance d from the center of the circle to the straight line and the radius r of the circle to judge or use the discriminant to judge the positional relationship between the straight line and the circle.
(2) Use the sum and difference of center distance d and radius to judge the positional relationship between two circles.
Focus F 1 (-c, 0), F2(c, 0)
(b2=a2-c2)
weird
collinearity equation
The focal radius | mf 1 | = a+ex0, | mf2 | = a-ex0.
Hyperbolic parabola
hyperbola
Focus F 1 (-c, 0), F2(c, 0)
(a,b>0,b2=c2-a2)
weird
collinearity equation
The focal radius | mf 1 | = ex0+a, | mf2 | = ex0-a parabola y2 = 2px (p > 0).
Focus f
collinearity equation
translation of axes
Here (h, k) is the coordinate of the origin of the new coordinate system in the original coordinate system.