## 104 Reputation

15 years, 175 days

## Solve giving incorrect solutions...

Maple 13

I'm trying to see when a matrix becomes singular, so I took its determinant and checked when it would vanish using solve.  The problem is that solve gives me a solution that doesn't satisfy the original equation, either symbolically or numerically.  Am I doing something wrong, or is this a bug in solve?

Here's what I'm getting:

WrongSolution.mw

## "#include" type directive for worksheets...

Maple

I have a worksheet that contains various pieces of a robot's dynamic and kinematic equations.  I want to perform different design tasks, taking the base model and working off of it.  I'd like to have only 1 model of the robot and not duplicate it across all of my different design worksheets because things change in the robot model as I switch up tooling, find better means of performing a system identification, etc.

Is there any functionality that would allow...

## Arrows and polar coordinates...

Maple

I'm trying to plot an arrow in polar coordinates.  Here's an example for an arrow who's base is at (1,Pi/4) pointing right with unit length.  It seems like the coords option is being ignored by plottools[arrow].

The following lines give me the same results in Maple:

plots[display](plottools[arrow]([1,Pi/4], [1,0], 0.05, 0.1, 0.1, coords=polar));

plots[display](plottools[arrow]([1,Pi/4], [1,0], 0.05, 0.1, 0.1));

Is this a bug?

Kevin

## Conversion from complex exponentials to ...

Maple
I'm trying to put together an analysis of a damped harmonic oscillator for a tutorial and I can't get the answer into the form I'd like. If you have a complex exponential, you can easily express it as a sum of a sin and cos using the convert function with the 'trig' option. If you have a term in the exponent that always evaluates to complex value because of the assumptions on your variables, however, it will always write the expression in terms of sinh and cosh. Is there any way to force Maple to put the solution in terms of sin and cos?