**(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