zs

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

受欢迎的三角函数 >

sin(6x)cos(9x)-cos(6x)sin(9x)=-0.4

解答

sin (6 x) cos (9 x) - cos (6 x) sin (9 x) = - 0.4

解答

x = \frac{0.41151 \dots}{3} - \frac{2 πn}{3}, x = - \frac{π}{3} - \frac{0.41151 \dots}{3} - \frac{2 πn}{3}

+1

度数

x = 7.85939 \dots^{\circ} - 12 0^{\circ} n, x = - 67.85939 \dots^{\circ} - 12 0^{\circ} n

求解步骤

sin (6 x) cos (9 x) - cos (6 x) sin (9 x) = - 0.4

使用三角恒等式改写

sin (6 x) cos (9 x) - cos (6 x) sin (9 x)

使用角差恒等式:

sin (s) cos (t) - cos (s) sin (t) = sin (s - t)

= sin (6 x - 9 x)

sin (6 x - 9 x) = - 0.4

使用反三角函数性质

sin (6 x - 9 x) = - 0.4

sin (6 x - 9 x) = - 0.4

的通解

sin (x) = - a \Rightarrow x = arcsin (- a) + 2 πn, x = π + arcsin (a) + 2 πn

6 x - 9 x = arcsin (- 0.4) + 2 πn, 6 x - 9 x = π + arcsin (0.4) + 2 πn

6 x - 9 x = arcsin (- 0.4) + 2 πn, 6 x - 9 x = π + arcsin (0.4) + 2 πn

解

6 x - 9 x = arcsin (- 0.4) + 2 πn : x = \frac{arcsin ( \frac{2}{5} )}{3} - \frac{2 πn}{3}

6 x - 9 x = arcsin (- 0.4) + 2 πn

化简

6 x - 9 x : - 3 x

6 x - 9 x

同类项相加:

6 x - 9 x = - 3 x

= - 3 x

化简

arcsin (- 0.4) + 2 πn : - arcsin (\frac{2}{5}) + 2 πn

arcsin (- 0.4) + 2 πn

arcsin (- 0.4) = - arcsin (\frac{2}{5})

arcsin (- 0.4)

= arcsin (- \frac{2}{5})

利用以下特性:

arcsin (- x) = - arcsin (x)

arcsin (- \frac{2}{5}) = - arcsin (\frac{2}{5})

= - arcsin (\frac{2}{5})

= - arcsin (\frac{2}{5}) + 2 πn

- 3 x = - arcsin (\frac{2}{5}) + 2 πn

两边除以

- 3

- 3 x = - arcsin (\frac{2}{5}) + 2 πn

两边除以

- 3

\frac{- 3 x}{- 3} = - \frac{arcsin ( \frac{2}{5} )}{- 3} + \frac{2 πn}{- 3}

化简

\frac{- 3 x}{- 3} = - \frac{arcsin ( \frac{2}{5} )}{- 3} + \frac{2 πn}{- 3}

化简

\frac{- 3 x}{- 3} : x

\frac{- 3 x}{- 3}

使用分式法则:

\frac{- a}{- b} = \frac{a}{b}

= \frac{3 x}{3}

数字相除:

\frac{3}{3} = 1

= x

化简

- \frac{arcsin ( \frac{2}{5} )}{- 3} + \frac{2 πn}{- 3} : \frac{arcsin ( \frac{2}{5} )}{3} - \frac{2 πn}{3}

- \frac{arcsin ( \frac{2}{5} )}{- 3} + \frac{2 πn}{- 3}

使用分式法则:

\frac{a}{- b} = - \frac{a}{b}

= - (- \frac{arcsin ( \frac{2}{5} )}{3}) + \frac{2 πn}{- 3}

使用分式法则:

\frac{a}{- b} = - \frac{a}{b}

= - (- \frac{arcsin ( \frac{2}{5} )}{3}) - \frac{2 πn}{3}

使用法则

- (- a) = a

= \frac{arcsin ( \frac{2}{5} )}{3} - \frac{2 πn}{3}

x = \frac{arcsin ( \frac{2}{5} )}{3} - \frac{2 πn}{3}

x = \frac{arcsin ( \frac{2}{5} )}{3} - \frac{2 πn}{3}

x = \frac{arcsin ( \frac{2}{5} )}{3} - \frac{2 πn}{3}

解

6 x - 9 x = π + arcsin (0.4) + 2 πn : x = - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} - \frac{2 πn}{3}

6 x - 9 x = π + arcsin (0.4) + 2 πn

同类项相加:

6 x - 9 x = - 3 x

- 3 x = π + arcsin (0.4) + 2 πn

两边除以

- 3

- 3 x = π + arcsin (0.4) + 2 πn

两边除以

- 3

\frac{- 3 x}{- 3} = \frac{π}{- 3} + \frac{arcsin ( 0.4 )}{- 3} + \frac{2 πn}{- 3}

化简

\frac{- 3 x}{- 3} = \frac{π}{- 3} + \frac{arcsin ( 0.4 )}{- 3} + \frac{2 πn}{- 3}

化简

\frac{- 3 x}{- 3} : x

\frac{- 3 x}{- 3}

使用分式法则:

\frac{- a}{- b} = \frac{a}{b}

= \frac{3 x}{3}

数字相除:

\frac{3}{3} = 1

= x

化简

\frac{π}{- 3} + \frac{arcsin ( 0.4 )}{- 3} + \frac{2 πn}{- 3} : - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} - \frac{2 πn}{3}

\frac{π}{- 3} + \frac{arcsin ( 0.4 )}{- 3} + \frac{2 πn}{- 3}

使用分式法则:

\frac{a}{- b} = - \frac{a}{b}

= - \frac{π}{3} + \frac{arcsin ( 0.4 )}{- 3} + \frac{2 πn}{- 3}

使用分式法则:

\frac{a}{- b} = - \frac{a}{b}

= - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} + \frac{2 πn}{- 3}

使用分式法则:

\frac{a}{- b} = - \frac{a}{b}

= - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} - \frac{2 πn}{3}

x = - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} - \frac{2 πn}{3}

x = - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} - \frac{2 πn}{3}

x = - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} - \frac{2 πn}{3}

x = \frac{arcsin ( \frac{2}{5} )}{3} - \frac{2 πn}{3}, x = - \frac{π}{3} - \frac{arcsin ( 0.4 )}{3} - \frac{2 πn}{3}

以小数形式表示解

x = \frac{0.41151 \dots}{3} - \frac{2 πn}{3}, x = - \frac{π}{3} - \frac{0.41151 \dots}{3} - \frac{2 πn}{3}

作图

流行的例子

sin^2(x)=2tan^2(x)

sin^{2} (x) = 2 tan^{2} (x)

cos^3(x)=cos(2x+x)

cos^{3} (x) = cos (2 x + x)

solvefor x,(d^2-3d+2)y=sin(e^x)

so l v e f or x, (d^{2} - 3 d + 2) y = sin (e^{x})

cos(6x)+cos(2x)=0

cos (6 x) + cos (2 x) = 0

2sin^2(45-a)=1-sin^2(a)

2 sin^{2} (4 5^{\circ} - a) = 1 - sin^{2} (a)