Cast Diagram Negative. From the above diagram the sine wave is. The other two trig fractions are negative.
Positive in quadrants 1 2 above the x axis negative in quadrants 3 4 below the x axis repeating the above for cosine tan a cast diagram can be drawn. A all sine tan cosine positive 0 90 s sine positive 90 180 t tan positive 180 270. From the above diagram the sine wave is.
So if you want to find sinx 0 5 x is 30 from your calculator.
In this video i introduc. Trigonometry at as a level includes solving trigonometric equations and finding multiple solutions using a cast diagram or graph. In the third quadrant only the values for tan are positive. Positive in quadrants 1 2 above the x axis negative in quadrants 3 4 below the x axis.
