HP 48GII

Computer Algebra Commands 4-73
TAN2SC2
Type: Command
Description: Replaces tan(x) terms in an expression with sin(2x)/1+cos(2x) terms.
Access: PTRIG, Trigonometry, …ÑL
Input: An expression
Output: The transformed expression.
Flags: Exact mode must be set (flag –105 clear).
Numeric mode must not be set (flag -3 clear).
Radians mode must be set (flag –17 set).
I
n previous versions of the CAS, if flag –116 was set (Prefer sin()), then TAN2SC2 replaced tan(x)
terms with: 1 – Cos(2x)/Sin(2x). This action is now performed by the TAN2CS2 command.
Example: Replace tan(x) terms in the function:
x
( )
tan
( )
2
Command:
TAN2SC2(TAN(X)^2)
Result: (SIN(2*X)/(1+COS(2*X)))^2
See also: HALFTAN, TAN2CS2, TAN2SC
TAYLOR0
Type: Function
Description: Performs a fourth-order Taylor expansion of an expression at x = 0.
Access: Calculus, !Ö LIMITS & SERIES, PCALC L
Input: An expression
Output: The Taylor expansion of the expression.
Flags: Exact mode must be set (flag –105 clear).
Numeric mode must not be set (flag -3 clear).
Radians mode must be set (flag –17 set).
Example: Obtain the fourth-order Taylor series expansion of cos(x) at x=0.
Command:
TAYLOR0(COS(X))
Result: 1/24*X^4+-1/2*X^2+1
See also: DIVPC, lim, TAYLR, SERIES
TCHEBYCHEFF
Type: Function
Description: Returns the nth Tchebycheff polynomial.
Access: Catalog, …µ
Input: A non-negative integer, n.
Output: The nth Tchebycheff polynomial.
Flags: Exact mode must be set (flag –105 clear).
Numeric mode must not be set (flag -3 clear).
Example: Obtain the fourth Tchebycheff polynomial.
Command:
TCHEBYCHEFF(4)
Result: 8*X^4-8*X^2+1
See also: HERMITE, LEGENDRE