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**Signs of the trigonometric functions in the second quadrant**
Second Quadrant	Notation
	[math]\text{P is any point in the second quadrant}\,[/math] [math]\overline {ON}\text{ x-coordinate or abscissa of point P, negative}\,[/math] [math]\overline {OM}\text{ y-coordinate or ordinate of point P, positive}\,[/math] [math]\overline {OP}\text{ distance from the origin, always}\,[/math] [math]\text{positive because it is a length}\,[/math] [math]\overline {OM}=\overline{NP}\,[/math]
[math]\sin \alpha=\frac{\overline{NP}}{\overline {OP}}=\frac{\text{y-coordinate}}{\text{distance from the origin}}=\frac{a}{b}\qquad \color{Red}+[/math]
[math]\cos \alpha=\frac{\overline{ON}}{\overline {OP}}=\frac{\text{x-coordinate}}{\text{distance from the origin}}=\frac{-c}{b}\qquad \color{Red}-[/math]
[math]\tan \alpha=\frac{\overline{NP}}{\overline {ON}}=\frac{\text{y-coordinate}}{\text{x-coordinate}}=\frac{a}{-c}\qquad \color{Red}-[/math]
[math]\cot \alpha=\frac{\overline{ON}}{\overline {NP}}=\frac{\text{x-coordinate}}{\text{y-coordinate}}=\frac{-c}{a}\qquad \color{Red}-[/math]
[math]\sec \alpha=\frac{\overline{OP}}{\overline {ON}}=\frac{\text{distance from the origin}}{\text{x-coordinate}}=\frac{b}{-c}\qquad \color{Red}-[/math]
[math]\csc \alpha=\frac{\overline{OP}}{\overline {NP}}=\frac{\text{distance from the origin}}{\text{y-coordinate}}=\frac{b}{a}\qquad \color{Red}+[/math]

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