Math

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General math discussion

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  1. Basic, then advanced

    Though the videos on Khan Academy's section for math are useful, they are not as helpful as they could be. Being an eight grade student, the math problems are becoming more advanced, thus bringing me to my suggestion. Khan Academy should have basic/easier problem(s) for the younger or less experienced viewers in the beginning of the videos and more advanced problems for those of older age or higher experienced in that specific form of math toward the end.

    Thank You!

    1 vote
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    • Comparing Ratios: higher and lower

      What is a "Higher Ration" versus a "lower ratio"? Is it merely lower when the ration is near equal on both sides (5:6 is lower than 1:18 or 18:1)? OR is is computed like a fraction where 1:4 (1/4) is lower than 3:4 (3/4) in which case order matters....4:3 is higher

      1 vote
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      • Need Help

        First of all i wana thanks Sal for this wonderful website. i am preparing for an entrance exam but i got struck in geometry section can Anyone help me I will be thankful to him :)

        4 votes
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        • Zero=Imaginary Unit

          Help! I think I proved 0=i!

          e^(i2π )=1
          ln(1)=i2π
          (ln(1))/2π =i
          log base anything of 1 = 0, since x^0 always =1
          0/2π =i
          0=i

          Please show what I did wrong! I don't wanna be the person who killed algebra!

          1 vote
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          • Should We do something like for college in test prep or there already one for college.

            When college people go to khan is there something for them to do? If not,maybe we could include something for them.

            9 votes
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            • You guys should make it easier to find practice tests, and gain points.

              I am taking calculus in the fall, and my teacher is requiring that each future student gets 400,000 energy points over the summer, to keep up our skill. However, I have spent nearly 4 hours so far doing Mastery Challenges, and practice problems, and have only acquired around 50,000 points. Any ideas or help?

              5 votes
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                1 comment  ·  Admin →
              • You guys should have a leaderboard

                You guys should have a leaderboard

                5 votes
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                • Problems with "Describing Distributions With Center And Spread" module. (6th Grade, Data and Statistics)

                  In nearly all of the questions contained in this module, you are instructed to find the "interquartile range" of a data set in either a box-and-whisker or dot plot. However, that term is never defined in any of the preceding videos. I was forced to look it up on Wikipedia just to understand what the module was referring to.

                  Furthermore, in the preceding videos, "quartiles" were defined in the context of box-and-whisker plots, but in this module you are frequently required you to apply the quartile concept to dot plots -a method not covered in any of the preceding videos.…

                  3 votes
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                  • Highschool Geometry

                    I really like the current highschool geometry course, but I really would appreciate the practice and appliance of proofs and indirect at that in the problems.

                    3 votes
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                    • more missions needed

                      Math topics like Recreational Math are not missions so they do not show up as problems in the mastery challenges on the dashboard. Please make the math concepts that are not part of missions into new missions so you can get them on the mastery challenges.

                      2 votes
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                      • I need help.

                        I get volume, no problem, easy sailing, but surface area, ugh, forget about it!!! Could someone please help me?!?

                        7 votes
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                        • 5 votes
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                            1 comment  ·  Admin →
                          • Limits topic problem: Videos in wrong order

                            So I am watching the whole Limits series and its the second time when the order things seems wrong.

                            Firstly explanation on how the limit depends on the side you are approaching it comes after the practice tasks that require one to already know this. (Practice: One Sided Limits from graphs, explanation video: Limit at a point of discontinuity)
                            Secondly as i move further in videos in this one: Limit and function defined at point of discontinuity, at 3:45 or so Sal says; "lets use epsilon delta definition of limits to......"
                            But the epsilon-delta definition video is 24 videos AFTER…

                            2 votes
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                            • Problem practice before explanatory video

                              Hello, so I am into Limits at this moment and came arcoss the problem, that I stated above - practice before explanation.

                              So i did the exercise called: "one sided limits from graphs" and did not uderstand what is the correct answer when for example function had a jump at point and equaled 5 and 1 at the same time, so i didnt understand what was the correct limit at that particular point. So a moment later whan i watched this: https://www.khanacademy.org/math/differential-calculus/limits_topic/calculus-estimating-limits-graph/v/limit-at-a-point-of-discontinuity video I understood how to see the right limit (depends from which side function approaches the limit) and…

                              1 vote
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                              • New settings and sections in math 9th 10th etc...

                                include more grades and add your location to give new common core standards to people in states that have common core.

                                7 votes
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                                • 1 vote
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                                  • 1 vote
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                                    • 8 votes
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                                      • keep compass size

                                        On construction problems, I tink it would be better not to take some random size but to keep the last compass "size" to make it easier to draw medians.
                                        When I use a real compass, I don't change it until i'm sure I have finished

                                        2 votes
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                                          1 comment  ·  Admin →
                                        • Divisibility Test

                                          My student try to select "Yes" and the answer gave Incorrect to him. In other oportunity he tries do select "No" for the same exercise and the answer gave Incorrect again. What´s happen?

                                          2 votes
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                                          ← Previous 1 3 4 5 8 9

                                          Math

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