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Question:
could u please prove all the trigonometric formulaes
Answer:

In trigonometry, there are a lot of formulas. We can not write all formulas but we are

listing some important formulas.

1. Trigonometric functions

sin α, cos α

tan α = sin α/cos α, α ≠ π/2 + nπ, n ∈ Z

cot α = cos α/sin α, α ≠ π + nπ, n ∈ Z

tan α * cot α = 1

sec α = 1/cos α, α ≠ π/2 + nπ, n ∈ Z

cosec α = 1/sin α, α ≠ π + nπ, n ∈ Z

2. Pythagorus Identiy:

sin2 α + cos2 α = 1

1 + tan2 α = sec2 α

1 + cot2 α = cosec2 α

3. Sum-Difference Formula:

sin (α + β) = sin α * cos β + cos α * sin β

sin (α - β) = sin α * cos β - cos α * sin β

cos (α + β) = cos α * cos β - sin α * sin β

cos (α - β) = cos α * cos β + sin α * sin β

tan (α + β) = (tan α + tan β)/(1 - tan α * tan β)

tan (α - β) = (tan α - tan β)/(1 + tan α * tan β)

Rest of formulas, you can see from the book or on our website.

Not what you are looking for? Go ahead and submit the question, we will get back to you.

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