Question
Solve the equation
θ={6π+kπ65π+kπ,k∈Z
Alternative Form
θ={30∘+180∘k150∘+180∘k,k∈Z
Alternative Form
θ≈{0.523599+kπ2.617994+kπ,k∈Z
Evaluate
4cos2(θ)−3=0
Add or subtract both sides
4cos2(θ)=3
Divide both sides
44cos2(θ)=43
Divide the numbers
cos2(θ)=43
Take the root of both sides of the equation and remember to use both positive and negative roots
cos(θ)=±43
Simplify the expression
cos(θ)=±23
Separate the equation into 2 possible cases
cos(θ)=23cos(θ)=−23
Calculate
More Steps

Evaluate
cos(θ)=23
Use the inverse trigonometric function
θ=arccos(23)
Calculate
θ=6πθ=611π
Add the period of 2kπ,k∈Z to find all solutions
θ=6π+2kπ,k∈Zθ=611π+2kπ,k∈Z
Find the union
θ={6π+2kπ611π+2kπ,k∈Z
θ={6π+2kπ611π+2kπ,k∈Zcos(θ)=−23
Calculate
More Steps

Evaluate
cos(θ)=−23
Use the inverse trigonometric function
θ=arccos(−23)
Calculate
θ=65πθ=67π
Add the period of 2kπ,k∈Z to find all solutions
θ=65π+2kπ,k∈Zθ=67π+2kπ,k∈Z
Find the union
θ={65π+2kπ67π+2kπ,k∈Z
θ={6π+2kπ611π+2kπ,k∈Zθ={65π+2kπ67π+2kπ,k∈Z
Solution
θ={6π+kπ65π+kπ,k∈Z
Alternative Form
θ={30∘+180∘k150∘+180∘k,k∈Z
Alternative Form
θ≈{0.523599+kπ2.617994+kπ,k∈Z
Show Solution

Rewrite the equation
x2−3y2=0
Evaluate
4cos2(θ)−3=0
Multiply both sides
4(rcos(θ))2−3r2=0
Solution
More Steps

Evaluate
4(rcos(θ))2−3r2
To covert the equation to rectangular coordinates using conversion formulas,substitute rcosθ for x
4x2−3r2
To covert the equation to rectangular coordinates using conversion formulas,substitute x2+y2 for r2
4x2−3(x2+y2)
Simplify the expression
x2−3y2
x2−3y2=0
Show Solution
