SUBSIM Radio Room Forums - I suck at math!!!!

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I suck at math!!!!

God I hate algebra!!!:damn:

Anyone know how to do this stuff? It's been like 10+ years since I've seen this stuff!

Evaluate and Simplify the problem

x2y – 3x – y when x = -1 and y = 1

Also, does anyone know of any good math websites where you can enter problems like these and get the answers and where it shows you how it solved the problem?

Substitute in the values and then do the sum:

x2y – 3x – y when x = -1 and y = 1

= (-1 * 2 * 1) - (3*-1) -1

= -2 - (-3) -1

= -2 + 3 -1

= 0

(I think)

Quote:

Originally Posted by lesrae

Substitute in the values and then do the sum:

x2y – 3x – y when x = -1 and y = 1

= (-1 * 2 * 1) - (3*-1) -1

= -2 - (-3) -1

= -2 + 3 -1

= 0

(I think)

Strange, by convention numerical factors are always written before the variables so x2y should really be written 2xy.
Otherwise it could be interpreted as x^2*y.

@SubSerpent

I suck at math too. Badly. :p

What do you think calculators are for? :ping:

hehe, maths? I had to take my GCSE twice - grade E 1st time, grade D second time.
Was always better at languages. :roll:

Now I have an impressive CAD program to work out all of my sums etc for drawing work. Who needs a pen and paper anymore?

Now I do something a little in line with algebra (in as much as it has alkward syntax and rules etc) but completely different:

Code:

;;; DRAWING / PLOT SETUP ROUTINE FOR ******** DRAWINGS 1:100 @A0

;;; SETS LIMITS AND LOCKED VPORT IN PSPACE WITH CORRECT PLOTTING

;;; SETTINGS BEFORE PROMPTING USER TO SAVEAS.

;;; CREATED BY **** **** : 10/10/06.





(DEFUN C:A0-100    ()

  ;; SWITCH TO M/SPACE

  (COMMAND "TILEMODE" "1")

  (COMMAND "ZOOM" "E")



  ;; SWITCH TO P/SPACE

  (COMMAND "TILEMODE" "0")



  ;; P/SPACE SETTINGS

  (COMMAND "LIMITS" "0,0" "1189,841")

  (COMMAND "GRID" "ON")

  (COMMAND "ZOOM" "E")

  (COMMAND "LAYER" "MAKE" "_VPORT" "")

  (COMMAND "VPORTS" "0,0" "1189,841")

  (COMMAND ".MSPACE" "ZOOM" "E")

  (COMMAND "ZOOM" "1/100XP" ".PSPACE")

  (COMMAND "REGENALL")



  ;;PLOT SETTINGS

  (COMMAND "-PLOT"     "Y"           "LAYOUT1"

       "\\\\ukleifile02\\HPCL30"   "OVERSIZE: ISO A0"

       "MILLIMETERS" "LANDSCAPE"   "NO"         "EXTENTS"

       "1:1"     "CENTER"      "NO"         "."

       "NO"         "NO"           "YES"         "NO"

       "NO"         "YES"           "NO"

      )



  ;; LOCK VPORT

  (COMMAND "VPORTS" "LOCK" "ON" "ALL" "")

  (COMMAND "ZOOM" "E")

  (COMMAND "LAYER" "SET" "0" "FREEZE" "_VPORT" "LOCK" "_VPORT" "")

  (COMMAND "REGENALL")



  ;; FINAL

  (INITDIA)

  (COMMAND "SAVEAS")



  (PRINC)



)



;; END DEFUN

It's fairly basic for CAD programing, but I'm getting there oh so slowly :rock: if you don't hear from me it's because I'm 'Lost In Stupid Parentheses' :arrgh!:

Yes, its defenatly 0, no doubt about it.