hp40g+.book Page 7 Friday, December 9, 2005 1:03 AM

1. Find the exact length of AB in centimetres.

2. Determine the equation of the line AB.

First method

Type:

 

STORE((-1,3),A)

and press .

Accept the change to Complex mode, if necessary.

Note that pressing returns the coordinates in complex form: –1+3i.

Now type:

STORE((-3,-1),B)

and press .

The coordinates this time are represented as –3+–1·i. The vector AB has coordinates B – A.

Type:

(B - A)

Press . The result is 25 .

Now apply the DROITE command to determine the equation of the line AB:

Complex

DROITE A

B

Pressing gives an intermediate result.

Step-by-Step Examples

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