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Trigonometry Before starting any calculations in volving trigonometry always check the angle
measure for degrees, radians or gr adients. If the angle measure isn‛t consistent
with the type of angle being used, all a nswers will be wrong. A D at the top of the
screen indicates that the calculator is set to degrees. An R indicates radians an d G
gradients. Gradients are NEVER used in trigonometry in Australian schools.
Set in degrees Set in radians
Instructions to change the calcula tor from degrees to radians or radians to
degrees are on page 5.
Entering trigonometric expres sions
Enter the trigonometric ratio followe d by the angle. The calculator will insert a left
hand bracket but entering a ‘close brackets‛ is not required.
Degrees, minutes and seconds
The x button is used for entering degrees, minutes and seconds . The button
sequence for entering 52
o 36‛ 14” is 52x36x14xp.
Using inverse trig
The following button sequence is re quired to solve the equation tanq = 1.56.
SHIFT l1.56. If the 1.56 is the result of the previo us calculation the
sequence SHIFT lM can be use d.