Education Technology

# Knowledge Base

## Solution 12209: Entering Measured Angles in Gradients on the TI-83 Plus Family, TI-84 Plus Family and TI-Nspire™ Handheld in TI-84 Plus Mode.

### How can I enter measured angles in gradients on a TI-83 Plus family, TI-84 Plus family or TI-Nspire handheld in TI-84 Plus mode?

The TI-83 Plus family, TI-84 Plus family and TI-Nspire handheld in TI-84 Plus mode do not have the capability of measuring an angle in gradients mode (only degrees and radians are used). Gradient is used widely in Europe by geographers and architectures. It is defined by setting the right angle (p/2, 90°) to 100 grads.

Angle in grads = angle in degree x (400/360)

Angle in degree = angle in grads x (360/400)

A simple work around is to stay in radian mode and to define two conversion constants:

400/(2p) ® RG
2pi/400 ® GR

Which can be used as: sin(20GR) in order to calculate the sine of 20 grads sin-1(0.9)RG in order to calculate the angle in grads which corresponds to a sin of 0.9.

Please Note: To display the ® symbol, users will have to press the [STO®] key.

Please see the TI-83 family and TI-84 Plus family guidebooks for additional information.

Please Note: TI-Nspire handheld in TI-84 Plus mode users may refer to the TI-84 Plus family guidebook.