- #1
BOAS
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Hello,
i'm looking for an explanation of a rule I used to solve a problem. I came to the correct answer in the end, but I do not understand why my first attempt went wrong.
Find the general solution to cot4θ = tan5θ
tanA = tanB => A = nπ + B
tanα = a/b = cotβ
Where α and β are complementary angles.
cot4θ = tan5θ
tan(π/2 - 4θ) = tan5θ
π/2 - 4θ = nπ + 5θ
9θ = π/2 - nπ
θ = π/18 (2n - 1)
The above is not given as a solution in my book and the following is said to be correct.
5θ = nπ + π/2 - 4θ
9θ = nπ + π/2
θ = π/18 (2n + 1)
Why is this?
Thanks!
i'm looking for an explanation of a rule I used to solve a problem. I came to the correct answer in the end, but I do not understand why my first attempt went wrong.
Homework Statement
Find the general solution to cot4θ = tan5θ
Homework Equations
tanA = tanB => A = nπ + B
tanα = a/b = cotβ
Where α and β are complementary angles.
The Attempt at a Solution
cot4θ = tan5θ
tan(π/2 - 4θ) = tan5θ
π/2 - 4θ = nπ + 5θ
9θ = π/2 - nπ
θ = π/18 (2n - 1)
The above is not given as a solution in my book and the following is said to be correct.
5θ = nπ + π/2 - 4θ
9θ = nπ + π/2
θ = π/18 (2n + 1)
Why is this?
Thanks!