a/sinA=b/sinB=c/sinC=2R

note:

In ...

rare

Represents the radius of the circumscribed circle of a triangle.

cosine theorem

b^2=a^2+c^2-2accosB

Note: Angle B is the included angle between side A and side C..

the standard equation of the circle

(x-a)^2+(y-b)^2=^r2

Note: (a, b) is the central coordinate.

Circular general equation

x^2+y^2+Dx+Ey+F=0

Note: d 2+e 2-4f > 0

Parabolic standard equation

y^2=2px

y^2=-2px

x^2=2py

x^2=-2py

Transverse area of right prism

S=c*h

Oblique prism side area

S=c'*h

Side area of regular pyramid

S= 1/2c*h '

Transverse area of regular prism

S= 1/2(c+c')h '

Yuantai lateral area

s = 1/2(c+c’)l = pi(R+R)l

Surface area of ball

S=4pi*r2

Cylindrical side area

S=c*h=2pi*h

Cone lateral area

S= 1/2*c*l=pi*r*l

Arc length formula

l=a*r

A is the radian number r of the central angle

& gt0

Sector area formula

s= 1/2*l*r

Cone volume formula

V= 1/3*S*H

Cone volume formula

V= 1/3*pi*r2h

Oblique prism volume

V=S'L

Note: where s' is the area of the straight line,

L is the length of the side.

Cylinder volume formula

V=s*h

cylinder

V=pi*r2h

Double angle formula

tan2A=2tanA/[ 1-(tanA)^2]

cos2a=(cosa)^2-(sina)^2=2(cosa)^2

- 1= 1-2(sina)^2

half-angle formula

sin(A/2)=√(( 1-cosA)/2)

sin(A/2)=-√(( 1-cosA)/2)

cos(A/2)=√(( 1+cosA)/2)

cos(A/2)=-√(( 1+cosA)/2)

tan(A/2)=√(( 1-cosA)/(( 1+cosA))

tan(A/2)=-√(( 1-cosA)/(( 1+cosA))

cot(A/2)=√(( 1+cosA)/(( 1-cosA))

cot(A/2)=-√(( 1+cosA)/(( 1-cosA))

Sum difference product

2sinAcosB=sin(A+B)+sin(A-B)

2cosAsinB=sin(A+B)-sin(A-B)

)

2cosAcosB=cos(A+B)-sin(A-B)

-2sinAsinB=cos(A+B)-cos(A-B)

sinA+sinB = 2 sin((A+B)/2)cos((A-B)/2

cosA+cosB = 2cos((A+B)/2)sin((A-B)/2)

tanA+tanB=sin(A+B)/cosAcosB

The sum of the first n terms of some series

1+2+3+4+5+6+7+8+9+…+n = n(n+ 1)/2

1+3+5+7+9+ 1 1+ 13+ 15+…+(2n- 1)= N2

2+4+6+8+ 10+ 12+ 14+…+(2n)= n(n+ 1)

five

1^2+2^2+3^2+4^2+5^2+6^2+7^2+8^2+…+n^2=n(n+ 1)(2n+ 1)/6

1^3+2^3+3^3+4^3+5^3+6^3+…n^3=n2(n+ 1)2/4

1 * 2+2 * 3+3 * 4+4 * 5+5 * 6+6 * 7+…+n(n+ 1)= n(n+ 1)(n+2)/3

Ordinary derivative formula

1.y=c(c is a constant)

y'=0

2.y=x^n

y'=nx^(n- 1)

3.y=a^x

y'=a^xlna

y=e^x

y'=e^x

4.y=logax

y'=logae/x

y=lnx

y'= 1/x

5.y=sinx

y'=cosx

6.y=cosx

y'=-sinx

7.y=tanx

y'= 1/cos^2x

8.y=cotx

y'=- 1/sin^2x

9.y=arcsinx

y'= 1/√ 1-x^2

10.y=arccosx

y'=- 1/√ 1-x^2

1 1.y=arctanx

y'= 1/ 1+x^2

12.y=arccotx

y'=- 1/ 1+x^2