I made a project to train mental math… for elementary transcendental functions lol Press the box to change your game mode, and the circle to start. You can test your skills with logarithms, roots and trigonometric functions. Here's some general tips to calculating these guys, since it's easy to find material on multiplication and division (vedic techniques, cross-multiplication, cross-division, abacus, etc.), but not as easy for these. HOW TO CALCULATE SQUAREROOTS Eg. Calculate the squareroot of 21. Make a guess, for example, x=5. 5^2=25, and we take the difference between this square and our goal, 25-21=4. Divide 4 by 2, then by our guess, 5, to get 0.4. Finally, subtract this from our guess to get 5-0.4=4.6. The actual answer is 4.58. We can improve this value by guessing more accurately, or repeating several times. HOW TO CALCULATE CUBEROOTS Mainly perfect cubes show up here, so I'll discuss that. Eg. Cuberoot of 13824 Split between last three digits and the rest to get 13 and 824. 13 is in between 2^3 and 3^3, so our first digit is 2. 13824 ends in a 4, and so through some modular arithmetic we get the last digit is 4 (this should be memorised), and hence, our answer is 24. HOW TO CALCULATE TRIG VALUES Memorise the table and interpolate in between values you didn't memorise lol. Eg. sin54 degrees I've memorised sin50=0.76 and sin55=0.81, since we have 54 degrees it's probably closer to 0.81, so we guess sin54=0.80. The actual answer is 0.809, which is pretty good. HOW TO CALCULATE LOGARITHMS Yet again the same technique lol. Memorise important values, combine them via prime factorisation and stuff, and approximate answers. HOW TO CALCULATE N-TH ROOTS Use your memorised logarithms. There's an easier approach, but I can't be bothered explaining it here lol, and it takes a bit of time to get used to. Visit these places to learn more: https://worldmentalcalculation.com/category/training/ https://worldmentalcalculation.com/advanced-calculation-methods/
