**(Common) CAS Commands in Home Mode**

**(udpated 4/17/2014)**

Two things to aware of:

1. Any command from the CAS mode to be used in the Home Mode, regardless of entry, must have a "CAS." prefix. Examples include CAS.diff, CAS.simplify, etc.

2. Algebraic (symbolic) objects need single quotes surrounding them. They can be called by pressing Shift+Parenthesis Key ().

3. Not all CAS commands work as expected in Home and Programming. My focus is on the Home mode.

**Simplify**: CAS, 1, 1

Syntax:

Non-RPN: CAS.simplify('expression')

RPN: Not recommended - as it will numerically evaluate the expression

**Expand**: CAS, 1, 3

Syntax: CAS.expand('expression')

RPN: Not recommended - as it will numerically evaluate the expression

Example: CAS.expand('(X+3)^2') returns X^2+6*X+9

**Factor**

There are two commands for factoring:

**Polynomial:**CAS.Factor: CAS, 1, 4

Non-RPN Syntax: CAS.factor('expression')

Example: CAS.Factor('X^2-5*X+4') returns (X-4)*(X-1)

**Integer:**CAS.ifactor: CAS, 5, 2

Non-RPN Syntax: CAS.ifactor(integer)

Example: CAS.ifactor(186) returns 2*3*31

RPN Syntax:

1: integer

CAS.ifactor(1), press Enter

**Differentiation**: CAS, 2, 1

Non-RPN Syntax: CAS.diff('expression')

Simplification may be needed. So call up CAS.simplify, put up single quotes using Shift+Parenthesis Key, key up to the expression, press Copy (soft key), then press Enter

Example:

CAS.diff('COS(X)*SIN(X)') returns -SIN(X)*SIN(X)+COS(X)*COS(X)

CAS.simplify('-SIN(X)*SIN(X)+COS(X)*COS(X)') returns 2*COS(X)^2-1

RPN Syntax:

1: 'f(X)'

CAS.diff(1), press Enter

**Update (4/17/2014): If the above does not work, try this syntax:**

**CAS.diff('expression', 'variable')**

**Example: CAS.diff('COS(X)*SIN(X)', 'X') returns -SIN(X)*SIN(X)+COS(X)*COS(X)**

**RPN:**

**2: 'expression'**

**1: 'variable'**

**CAS.diff(2), press enter**

**Integration**: CAS, 2, 2

Non-RPN Syntax: CAS.int('expression')

Simplification may be needed. So call up CAS.simplify, put up single quotes using Shift+Parenthesis Key, key up to the expression, press Copy (soft key), then press Enter

Example:

CAS.int('2*e^(4*X)') returns 2*e^(4*X)/4

CAS.simplify('2*e^(4*X)/4') returns e^(4*X)/2

Not recommended for RPN Entry

**Update (4/17/2014): If the above syntax does not work, try:**

**CAS.int('expression', 'variable')**

**Example:**

**CAS.int('2*X*e^(4*X)','X') returns 2*(4*X-1)/16*e^(4*X)**

**CAS.simplify('2*(4*X-1)/16*e^(4*X)') returns (4*X*e^(4*X) - e^(4*X))/8**

**Summation (Σ)**: CAS, 2, 5

Non-RPN Syntax: CAS.sum('expression', 'variable', start, end)

Example: CAS.sum('N^3','N',1,9) returns 2025

RPN Syntax:

4: 'expression'

3: 'variable'

2: start

1: end

CAS.sum(4) press Enter

Note: Start and End must be numerical limits.

**Solving**

I recommend

**zeros**and

**cZeros**, not solve and cSolve. The syntax is pretty much the same.

Access:

zeros: CAS, 3, 2

cZeros: CAS, 3, 4

If the equation is f(X) and we are solving for X:

Non-RPN Syntax: CAS.zeros('f(X)')

RPN Syntax:

1: 'f(X)'

CAS.zeros(1), press Enter

Example:

CAS.zeros('X^3-6') returns [1.81712059283]

If you are solving for variables other than X:

Non-RPN Syntax: CAS.zeros('expression', 'variable')

RPN Syntax:

2: 'expression'

1: 'variable'

CAS.zeros(2), press Enter

Got to include the variable!

Example:

CAS.zeros('R^3-6') returns [].

CAS.zeros('R^3-6','R') returns [1.81712059293]

Hope this helps and we will cover more of this subject in the future.

Eddie

This blog is property of Edward Shore. 2013

Thank you Eddie for showing how to prepare and execute some CAS commands in the Home mode.

ReplyDeleteHowever, after keying in most of these on the calculator, it felt slow and error prone versus just using CAS mode.

RPN (where CAS supported) seemed almost as quick as CAS mode.

I wish the RPN mode wasn't so limited in CAS abilities.

DeleteHelp: As advised, in home mode I enter CAS.diff('COS(X)*SIN(X)') but the calculator returns "0" instead of the differentiated function. This is typical of my results. My version info is 2013 11 25 (5447), CAS version 1.1.0-27

ReplyDeleteTry CAS.diff('COS(X)*SIN(X)','X') Hopefully that will work with Ver. 5447.

DeleteSince this blog entry was done with an earlier software version, I may be looking at updating this entry. Thanks,

Eddie

Thank for you. That worked beautifully. I might add that "Complex" needs to be unchecked to get the result you show. I'm a new owner going through painful acclimation. Love your blog. JFS.

ReplyDeleteThanks James!

DeleteEddie

Thanks Eddie for your insight. I was playing around with my new HP Prime and thought I would tackle something benign like Newton's method. I'm just not getting the syntax to call CAS.diff on my function defined as F1(x) in the Function Symbolic View for each of the iterations. I've tried "f := CAS.diff('F1','X');" but to no avail. Do you have ideas on this?

ReplyDeleteSorry for getting back to you so late.

DeleteOn the Function App, Symb View, what you want is to use the Derivative template. The Derivative Template on the top row, 4th column on the template touch menu.

Set up: F1(X) = (d f(T))/(d T = X)

d is the derivative symbol

T is a dummy variable

Example: (d T^3)/(d T = X)

Video on calculating derivatives on the HP Prime (general): https://www.youtube.com/watch?v=LXwLiPlKO2M&list=UU25vsJdvgf_doIgE8-Lu7Xw

Hope this helps, again, apologizes for being super late. :(

Eddie