What is the general solution for 2sin^2(θ)-sin(θ)=0,0<= θ<2pi ?

Q: What is the general solution for 2sin^2(θ)-sin(θ)=0,0<= θ<2pi ?

The general solution for 2sin^2(θ)-sin(θ)=0,0<= θ<2pi is θ= pi/6 ,θ=(5pi)/6 ,θ=0,θ=pi

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

2sin^2(θ)-sin(θ)=0,0<= θ<2pi

Solution

2 sin^{2} (θ) - sin (θ) = 0, 0 \leq θ < 2 π

Solution

θ = \frac{π}{6}, θ = \frac{5 π}{6}, θ = 0, θ = π

Degrees

θ = 3 0^{\circ}, θ = 15 0^{\circ}, θ = 0^{\circ}, θ = 18 0^{\circ}

Solution steps

2 sin^{2} (θ) - sin (θ) = 0, 0 \leq θ < 2 π

Solve by substitution

2 sin^{2} (θ) - sin (θ) = 0

Let:

sin (θ) = u

2 u^{2} - u = 0

2 u^{2} - u = 0 : u = \frac{1}{2}, u = 0

2 u^{2} - u = 0

Solve with the quadratic formula

2 u^{2} - u = 0

Quadratic Equation Formula:

For

a = 2, b = - 1, c = 0

u_{1, 2} = \frac{- ( - 1 ) \pm ( - 1 ) ^{2} - 4 \cdot 2 \cdot 0}{2 \cdot 2}

u_{1, 2} = \frac{- ( - 1 ) \pm ( - 1 ) ^{2} - 4 \cdot 2 \cdot 0}{2 \cdot 2}

(- 1)^{2} - 4 \cdot 2 \cdot 0 = 1

(- 1)^{2} - 4 \cdot 2 \cdot 0

(- 1)^{2} = 1

(- 1)^{2}

Apply exponent rule:

(- a)^{n} = a^{n},

n

is even

(- 1)^{2} = 1^{2}

= 1^{2}

Apply rule

1^{a} = 1

= 1

4 \cdot 2 \cdot 0 = 0

4 \cdot 2 \cdot 0

Apply rule

0 \cdot a = 0

= 0

= 1 - 0

Subtract the numbers:

1 - 0 = 1

= 1

Apply rule

1 = 1

= 1

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

Separate the solutions

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

u = \frac{- ( - 1 ) + 1}{2 \cdot 2} : \frac{1}{2}

\frac{- ( - 1 ) + 1}{2 \cdot 2}

Apply rule

- (- a) = a

= \frac{1 + 1}{2 \cdot 2}

Add the numbers:

1 + 1 = 2

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

Multiply the numbers:

2 \cdot 2 = 4

= \frac{2}{4}

Cancel the common factor:

2

= \frac{1}{2}

u = \frac{- ( - 1 ) - 1}{2 \cdot 2} : 0

\frac{- ( - 1 ) - 1}{2 \cdot 2}

Apply rule

- (- a) = a

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

Subtract the numbers:

1 - 1 = 0

= \frac{0}{2 \cdot 2}

Multiply the numbers:

2 \cdot 2 = 4

= \frac{0}{4}

Apply rule

\frac{0}{a} = 0, a \neq = 0

= 0

The solutions to the quadratic equation are:

u = \frac{1}{2}, u = 0

Substitute back

u = sin (θ)

sin (θ) = \frac{1}{2}, sin (θ) = 0

sin (θ) = \frac{1}{2}, sin (θ) = 0

sin (θ) = \frac{1}{2}, 0 \leq θ < 2 π : θ = \frac{π}{6}, θ = \frac{5 π}{6}

sin (θ) = \frac{1}{2}, 0 \leq θ < 2 π

General solutions for

sin (θ) = \frac{1}{2}

sin (x)

periodicity table with

2 πn

cycle:

x 0 \frac{π}{6} \frac{π}{4} \frac{π}{3} \frac{π}{2} \frac{2 π}{3} \frac{3 π}{4} \frac{5 π}{6} sin (x) 0 \frac{1}{2} \frac{2}{2} \frac{3}{2} 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} x π \frac{7 π}{6} \frac{5 π}{4} \frac{4 π}{3} \frac{3 π}{2} \frac{5 π}{3} \frac{7 π}{4} \frac{11 π}{6} sin (x) 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2}

θ = \frac{π}{6} + 2 πn, θ = \frac{5 π}{6} + 2 πn

θ = \frac{π}{6} + 2 πn, θ = \frac{5 π}{6} + 2 πn

Solutions for the range

0 \leq θ < 2 π

θ = \frac{π}{6}, θ = \frac{5 π}{6}

sin (θ) = 0, 0 \leq θ < 2 π : θ = 0, θ = π

sin (θ) = 0, 0 \leq θ < 2 π

General solutions for

sin (θ) = 0

sin (x)

periodicity table with

2 πn

cycle:

x 0 \frac{π}{6} \frac{π}{4} \frac{π}{3} \frac{π}{2} \frac{2 π}{3} \frac{3 π}{4} \frac{5 π}{6} sin (x) 0 \frac{1}{2} \frac{2}{2} \frac{3}{2} 1 \frac{3}{2} \frac{2}{2} \frac{1}{2} x π \frac{7 π}{6} \frac{5 π}{4} \frac{4 π}{3} \frac{3 π}{2} \frac{5 π}{3} \frac{7 π}{4} \frac{11 π}{6} sin (x) 0 - \frac{1}{2} - \frac{2}{2} - \frac{3}{2} - 1 - \frac{3}{2} - \frac{2}{2} - \frac{1}{2}

θ = 0 + 2 πn, θ = π + 2 πn

θ = 0 + 2 πn, θ = π + 2 πn

Solve

θ = 0 + 2 πn : θ = 2 πn

θ = 0 + 2 πn

0 + 2 πn = 2 πn

θ = 2 πn

θ = 2 πn, θ = π + 2 πn

Solutions for the range

0 \leq θ < 2 π

θ = 0, θ = π

Combine all the solutions

θ = \frac{π}{6}, θ = \frac{5 π}{6}, θ = 0, θ = π

Graph

Popular Examples

5sin^2(x)+2sin(x)=0

5 sin^{2} (x) + 2 sin (x) = 0

solvefor x,y^3+7y^2+y+7=2cos(x)solve for

x, y^{3} + 7 y^{2} + y + 7 = 2 cos (x)

cos(2x)-11cos(x)+6=0

cos (2 x) - 11 cos (x) + 6 = 0

solvefor x,sin(x)= 1/(sqrt(2))solve for

x, sin (x) = \frac{1}{2}

-2cos(x)+1=5cos(x)+0

- 2 cos (x) + 1 = 5 cos (x) + 0

Frequently Asked Questions (FAQ)

What is the general solution for 2sin^2(θ)-sin(θ)=0,0<= θ<2pi ?
The general solution for 2sin^2(θ)-sin(θ)=0,0<= θ<2pi is θ= pi/6 ,θ=(5pi)/6 ,θ=0,θ=pi