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 >

2sin^2(x)+sin(x)-6=0

解答

2 sin^{2} (x) + sin (x) - 6 = 0

解答

x \in R 无解

求解步骤

2 sin^{2} (x) + sin (x) - 6 = 0

用替代法求解

2 sin^{2} (x) + sin (x) - 6 = 0

令

: sin (x) = u

2 u^{2} + u - 6 = 0

2 u^{2} + u - 6 = 0 : u = \frac{3}{2}, u = - 2

2 u^{2} + u - 6 = 0

使用求根公式求解

2 u^{2} + u - 6 = 0

二次方程求根公式:

若

a = 2, b = 1, c = - 6

u_{1, 2} = \frac{- 1 \pm 1 ^{2} - 4 \cdot 2 ( - 6 )}{2 \cdot 2}

u_{1, 2} = \frac{- 1 \pm 1 ^{2} - 4 \cdot 2 ( - 6 )}{2 \cdot 2}

1^{2} - 4 \cdot 2 (- 6) = 7

1^{2} - 4 \cdot 2 (- 6)

使用法则

1^{a} = 1

1^{2} = 1

= 1 - 4 \cdot 2 (- 6)

使用法则

- (- a) = a

= 1 + 4 \cdot 2 \cdot 6

数字相乘:

4 \cdot 2 \cdot 6 = 48

= 1 + 48

数字相加:

1 + 48 = 49

= 49

因式分解数字:

49 = 7^{2}

= 7^{2}

使用根式运算法则:

n a^{n} = a

7^{2} = 7

= 7

u_{1, 2} = \frac{- 1 \pm 7}{2 \cdot 2}

将解分隔开

u_{1} = \frac{- 1 + 7}{2 \cdot 2}, u_{2} = \frac{- 1 - 7}{2 \cdot 2}

u = \frac{- 1 + 7}{2 \cdot 2} : \frac{3}{2}

\frac{- 1 + 7}{2 \cdot 2}

数字相加/相减:

- 1 + 7 = 6

= \frac{6}{2 \cdot 2}

数字相乘:

2 \cdot 2 = 4

= \frac{6}{4}

约分:

2

= \frac{3}{2}

u = \frac{- 1 - 7}{2 \cdot 2} : - 2

\frac{- 1 - 7}{2 \cdot 2}

数字相减:

- 1 - 7 = - 8

= \frac{- 8}{2 \cdot 2}

数字相乘:

2 \cdot 2 = 4

= \frac{- 8}{4}

使用分式法则:

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

= - \frac{8}{4}

数字相除:

\frac{8}{4} = 2

= - 2

二次方程组的解是:

u = \frac{3}{2}, u = - 2

u = sin (x)

代回

sin (x) = \frac{3}{2}, sin (x) = - 2

sin (x) = \frac{3}{2}, sin (x) = - 2

sin (x) = \frac{3}{2} :

无解

sin (x) = \frac{3}{2}

- 1 \leq sin (x) \leq 1

无解

sin (x) = - 2 :

无解

sin (x) = - 2

- 1 \leq sin (x) \leq 1

无解

合并所有解

x \in R 无解

作图

流行的例子

tan(θ)= 8/15 ,sin(θ)>0

tan (θ) = \frac{8}{15}, sin (θ) > 0

cos(x)=(86.6)/(100)

cos (x) = \frac{86.6}{100}

-6sin(θ)=-3sqrt(3)

- 6 sin (θ) = - 33

sin (d) = 0.81

solvefor t,16sin(t)cos(t)=6sin(t)

so l v e f or t, 16 sin (t) cos (t) = 6 sin (t)