Quick Math: Is tan(theta) + tan(theta) equal to tan(2theta)?

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tan(theta) + tan(theta) equals 2tan(theta), not tan(2theta). The correct formula for tan(2theta) is 2tan(theta)/(1-tan^2(theta)). Some users initially confused the addition of two tangent values with the tangent of a double angle. The discussion also touched on the ability to factor out constants in integrals, confirming that 2 can be taken out of the integral of tan(theta). Overall, the thread clarifies the misunderstanding around the tangent addition and double angle formulas.
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tan(theta) + tan(theta) is equal to tan(2theta) right? just want to make sure
 
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ProBasket said:
tan(theta) + tan(theta) is equal to tan(2theta) right? just want to make sure

No. tan(theta) + tan(theta) is just 2tan(theta).

tan(2theta)=2tan(theta)/(1-tan^2(theta))
 
NO...
tan \theta + tan \theta = 2 tan \theta = tan 2 \theta ( 1-tan^2 \theta)
 
yea first i thought that tan(theta) + tan(theta) was 2tan(theta), but it didnt make sense for some reason cause it's 2*tan(theta), if you did a integral, can you take out the 2? to look like 2\int tan(theta)

maybe I'm thinking too much, cause it's really really late right now, well I'm going to get some sleep. thanks for the help
 
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ProBasket said:
yea first i thought that tan(theta) + tan(theta) was 2tan(theta), but it didnt make sense for some reason cause it's 2*tan(theta)

Yes and what you have is 1*tan (theta) + 1*tan (theta).

if you did a integral, can you take out the 2? to look like 2\int tan(theta)

An integral. Yes you can take the 2 out. You missed the d(theta) as well :smile:.
 
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