HP 40gs - Page 213

Computer Algebra System (CAS) 14-31
Example 3
Typing:
LIN(SIN(X))
gives:
LNCOLLECT Regroup the logarithms
LNCOLLECT has as an argument an expression
containing logarithms.
LNCOLLECT regroups the terms in the logarithms. It is
therefore preferable to use an expression that has already
been factored (using FACTOR).
Typing:
LNCOLLECT(LN(X+1)+LN(X-1))
gives:
ln((x+1)(x−1))
POWEXPAND Transform a power
POWEXPAND writes a power in the form of a product.
Typing:
POWEXPAND((X+1)
3
)
gives:
(x+1) · (x+1) · (x+1)
This allows you to do the development of (x + 1)
3
in step
by step, using DISTRIB several times on the preceding
result.
SINCOS Transform the complex exponentials into sin and cos
SINCOS takes as an argument an expression containing
complex exponentials.
SINCOS then rewrites this expression in terms of sin(x)
and cos(x).
1
4
---
2 ix⋅⋅()–()exp⋅
1
2
---
1
4
---
2 ix⋅⋅()exp⋅++
i
2
---
ix⋅exp⋅
i
2
---
ix⋅()–()exp⋅+–
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