Radians and Transformations (1 Viewer)

[od9895]

HI
Could anyone please explain to me what is a radian and this rule is a cosx + b sinx = r cos(x+a)
Could you guys please show me how to use these rules and where to use those rules. Please provide a lot of examples of using both rules please.

Thanks

 

[nightweaver066]

I would recommend you thoroughly read the trigonometry section of a textbook.

Fitzpatrick or Cambridge would be good.

Some textbooks will derive them, but they all provide sufficient examples as to when to use the rules.

 

[RealiseNothing]

A radian is the ratio between a circle's arc and it's radius. More generally, it is an alternative to measuring angles in a ratio/numerical value rather than in degrees.

 

[Nooblet94]

HI
Could anyone please explain to me what is a radian and this rule is a cosx + b sinx = r cos(x+a)
Could you guys please show me how to use these rules and where to use those rules. Please provide a lot of examples of using both rules please.

Thanks

360 degrees = 2pi radians, that's basically all you need to know.

That rule's called the auxillary angle method. See http://trevorpythag.co.uk/2009/math...le-method-for-solving-trigonometry-equations/ for a pretty good explanation & example.

There's another method for solving that type of equation that I believe is called the t-formula method. I can't find a good explanation online and I really can't be bothered typing one out, but there should be one in your textbook.

EDIT: You should be able to use both methods as questions may ask something along the lines of "solve this equation using the auxillary angle method"