P polymath New member Joined Jan 27, 2011 Messages 3 Jan 27, 2011 #1 hello, xy +xy^2+xy^3=z where y and z are real numbers and x is unknown. Is there a way to isolate x?
mmm4444bot Super Moderator Joined Oct 6, 2005 Messages 10,958 Jan 27, 2011 #2 Yes. Factor out x, on the lefthand side. That should give you an idea.
P polymath New member Joined Jan 27, 2011 Messages 3 Jan 27, 2011 #3 what do you mean "factor out x"?
D Denis Senior Member Joined Feb 17, 2004 Messages 1,700 Jan 28, 2011 #4 polymath said: what do you mean "factor out x"? Click to expand... You don't know that? Surprising. Attending math classes? EXAMPLE: 2xy + 7x = x(2y + 7)
polymath said: what do you mean "factor out x"? Click to expand... You don't know that? Surprising. Attending math classes? EXAMPLE: 2xy + 7x = x(2y + 7)
P polymath New member Joined Jan 27, 2011 Messages 3 Jan 28, 2011 #5 okay. so we get x (y+y^2+y^3)=z x= z/(y+y^2+y^3) Now, is there something we can do to simply the y?
D Denis Senior Member Joined Feb 17, 2004 Messages 1,700 Jan 28, 2011 #6 polymath said: x= z/(y+y^2+y^3) Now, is there something we can do to simply the y? Click to expand... x = z / [y(y^2 + y + 1)] ; not much better! Anyhow, you're asked to isolate the x, NOT simplify the y's :idea:
polymath said: x= z/(y+y^2+y^3) Now, is there something we can do to simply the y? Click to expand... x = z / [y(y^2 + y + 1)] ; not much better! Anyhow, you're asked to isolate the x, NOT simplify the y's :idea:
