Welcome to the ACT math site for Ed-Co HS
Besides the original Trig functions, there are also three more methods to use: Cosecant, Secant, Cotangent
These functions are inverses of the normal trig functions. They may be used instead of the normal functions if the appropriate angles
or sides are present that make the inverses better choices for solving the triangle.
Cosecant: csc ø = the length of the hypotenuse = ___1___ length of the side opposite the angle sin ø Secant: sec ø = the length of the hypotenuse = ___1___ length of the side adjacent to the angle cos ø Cotangent: cot ø = length of the side adjacent to the angle = ___1___ length of the side opposite the angle tan øExample A biologist wants to know the width w of a river in order to properly set instruments for studying the pollutants in the river. From point A, the biologist walks downstream 100 feet and sights to point C. From this sighting, it is determined that ø = 58o . How wide is the river?
First Step: Find out what you know to draw the triangle.
Second Step: Find our what Trig function to use.
Third Step: Plug the numbers into the formula
Fourth Step: Solve for ø.
cot ø = adjacent
opposite
cot 58º = 100
X Solve for X cot 58º (X) =100 Get X by itself X = 100 cot 58 º X = 160.03 The river is 160.03 feet Wide !!!!