HP 50G, Руководство пользователя

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Use command SOLVE at this point (from the S.SLV menu:
„Î
) After about
40 seconds, maybe more, you get as result a list:
{ ‘t = (x-x0)/(COS(
θ
0)*v0)’
‘y0 = (2*COS(
θ
0)^2*v0^2*y+(g*x^2(2*x0*g+2*SIN(
θ
0))*COS(
θ
0)*v0^2)*x+
(x0^2*g+2*SIN(
θ
0)*COS(
θ
0)*v0^2*x0)))/(2*COS(
θ
0)^2*v0^2)’]}
Press
μ
to remove the vector from the list, then use command OBJ , to get
the equations listed separately in the stack.
Example 2 – Stresses in a thick wall cylinder
Consider a thick-wall cylinder for inner and outer radius a and b , respectively,
subject to an inner pressure P
i
and outer pressure P
o
. At any radial distance r
from the cylinder’s axis the normal stresses in the radial and transverse
directions,
σ
rr
and
σ
θθ
, respectively, are given by
Notice that the right-hand sides of the two equations differ only in the sign
between the two terms. Therefore, to write these equations in the calculator, I
suggest you type the first term and store in a variable T1, then the second term,
and store it in T2. Writing the equations afterwards will be matter of recalling
Note : This method worked fine in this example because the unknowns t and
y0 were algebraic terms in the equations. This method would not work for
solving for
θ
0, since
θ
0 belongs to a transcendental term.
,
) (
) (
2 2 2
2 2
2 2
2 2
a b r
P P b a
a b
P b P a
o i o i
− ⋅
− ⋅ ⋅
+
−
⋅ − ⋅
=
θθ
σ
.
) (
) (
2 2 2
2 2
2 2
2 2
a b r
P P b a
a b
P b P a
o i o i
rr
− ⋅
− ⋅ ⋅
−
−
⋅ − ⋅
=
σ