Did you know that the signs of the trigonometric ratios can be remembered by the phrase “ALL SILVER TEA CUPS “?
A in “All” stands for all the ratios in the first quadrant are positive
S in the “Silver” is for Sine and Cosecant in the second quadrant are alone positive
T in “Tea” is for Tan and Cotangent in the third quadrant are alone positive and
C in the “Cups” for the Cosine and Secant in the 4th quadrant are alone positive.
Here are a couple of examples on Clay6 for the above tip http://clay6.com/qa/1046/ and http://clay6.com/qa/1000