+- HP Forums (https://www.hpmuseum.org/forum)
+-- Forum: HP Calculators (and very old HP Computers) (/forum-3.html)
+--- Forum: HP Prime (/forum-5.html)
+--- Thread: [CAS] ABS EXPAND new cmd (/thread-7989.html)
[CAS] ABS EXPAND new cmd - compsystems - 03-21-2017 05:03 AM
solve((r^2) = ((r*sin(x)-4)^2),r); returns
{ (4/(sin(x)-1)), (4/(sin(x)+1)) }
Early transcendentals by Dennis G. Zill and others ... book show
r^2 = (r*sin(x)-4)^2
√(r^2) = √((r*sin(x)-4)^2)
r = +(r*sin(x)-4) or r = -(r*sin(x)-4)
r-r*sin(x) = -4 or r+r*sin(x) = -4
r*(1-sin(x)) = -4 or r*(1+sin(x)) = -4
r = -4/(1-sin(x)) or r = -4/(1+sin(x))
You can see the importance ABS EXPAND command, which is available in the CLASPAD400 And I wish please, that Bernard can also include him in the xCAS.