$$Introduction:$$

Hello! You have reached the "Great answers to learn from" page. This page is meant to be a collection of great answers that people could look back upon and learn from. Hopefully if you have a certain topic you want to learn about, you can some posts on that topic here!

For the most part, this thread is organized into "grade levels" of mathematics to make it easier to find what you want to learn about.

Finally, if you have anything you want to add to this post, go ahead and reply to it with what you want added, or you can message me and I'll add it to the proper section.

**Roots and exponents:**

• Simplifying.

http://web2.0calc.com/questions/3-sup3-radic-24-sup3-radic-375

http://web2.0calc.com/questions/can-anyone-do-square-roots

• Finding a root of a negative number

• Rationalising a denominator:

http://web2.0calc.com/questions/in-question-21-nbsp

• Exponets with negative bases:

**Fractions:**

• Dividing two fractions:

http://web2.0calc.com/questions/3-4-5-8

• Find the Least Common Denominator (LCD):

http://web2.0calc.com/questions/what-is-the-lcd-for-5-9-and-2-3

**Dealing with time in math, on a handheld calculator!**

http://web2.0calc.com/questions/what-is-21hours-and-58-minutes-subtracted-by-4-36-p-m-equal

**Directed numbers and plotting on a number line**

http://web2.0calc.com/questions/the-answer-to-the-expression-3-6-located-on-a-horizontal-number-line

**Is zero even or odd?**

http://web2.0calc.com/questions/0-is-a-nbsp-odd-number-or-even-number-why-please-explain

**Speed and rates:**

• Migrating elephants!

• Speed of a current

**Comparing numbers; the apparent brightness of stars!**

http://web2.0calc.com/questions/science-link-math-question

**Percentages:**

• Find a total when given a part

http://web2.0calc.com/questions/435-is-15-of-what-number

**Variant of Average:**

**Adding up all the numbers between two specific numbers:**

http://web2.0calc.com/questions/what-is-all-the-numbers-from-1-to-100-added-up

**Forever repeating decimal!**

http://web2.0calc.com/questions/0-99999

**Order of operations - multiplication before addition:**

http://web2.0calc.com/questions/3x60-5x9-2x2

**The basics of algebra:**

• What does "x" mean?

http://web2.0calc.com/questions/5x-21-2x-what-does-x-mean

• Solving for x by "balancing" out two sides of an equation:

http://web2.0calc.com/questions/solve-for-x-7

• Why would I use x^{2}?

http://web2.0calc.com/questions/what-does-x-squared-equal

**Algebra word problem examples:**

• Simultaneous equations:

http://web2.0calc.com/questions/how-old-they-are

• Set it up algebraicly, and solve!

http://web2.0calc.com/questions/i-know-the-answer-but-do-not-know-how-to-do-the-work

**Fractions and solving for x:**

http://web2.0calc.com/questions/if-then

http://web2.0calc.com/questions/solve-for-x-3-over-4-x-5-over-8-4x

**Three different techniques to this answer dealing with polynomials:**

http://web2.0calc.com/questions/5a-5-5a-5

**Imaginary numbers:**

• Introduction to imaginary numbers

http://web2.0calc.com/questions/help-me-with-solving-this-equation-please

• Finding Complex Roots with imaginary numbers (Difficult)

http://web2.0calc.com/questions/how-do-i-solve-the-sqrt4-16-complex-numbers-4-different-roots

• Complex number proof that i^{i} is a real number:

http://web2.0calc.com/questions/puzzle-question-i-i

**Difficult inequality solution**

http://web2.0calc.com/questions/how-can-i-solve-the-first-question-nbsp

**Solveing a nonlinear inequality. This one looks like a parabola!**

http://web2.0calc.com/questions/solve-the-nonlinear-inequality

**Well explained by heureka:**

http://web2.0calc.com/questions/5x-8-3x-3-whats-the-x

**Heureka just being awesome:**

http://web2.0calc.com/questions/solve-the-equation_1

**An example of scientific notation:**

**A more complicated algebra question answered by Alan**

http://web2.0calc.com/questions/x-2-xy-y-2-28-y-2-x-how-do-you-get-x-and-y

**Horizontal and slant Asymtotes (Advanced)**

http://web2.0calc.com/questions/horizontal-asymptote-of-y-x-2-6x-3-x-3

**Quadratic equations:**

• Complicated one:

http://web2.0calc.com/questions/please-help_40

• Solving with the quadratic formula:

http://web2.0calc.com/questions/help-me-with-solving-this-equation-please

• A little different than the usual quadratic questions:

http://web2.0calc.com/questions/x-7sqrt-x-10-0

**Finding the equation of a polynomial when you are given the roots:**

**Linear Representation (graphing the equation of a line) of a worded problem:**

**What is a logarithm? (thanks to anonymous)**

http://www.mathsisfun.com/algebra/logarithms.html

**Half life problem:**

**Solving for x when x is raised to a power:**

http://web2.0calc.com/questions/can-t-seem-to-get-this-equation-solved

**Finding why an equation with logs equals zero - two different approaches:**

http://web2.0calc.com/questions/why-does-log-2ab-log-5-a-log10b-0

**Radioactive decay!**

**This certainly looks like a more difficult logarithmic equation to me!**

http://web2.0calc.com/questions/difficult-logarithmic-equation-without-a-calculator

**Harder logarithm problem. Three people got the same answer, so it should be right!**

http://web2.0calc.com/questions/log-3-6-log-9-6-log-4-6-log-18-6

**Triangles! Great picture and explanation by CPhill**

**Finding the circumference from the diameter:**

http://web2.0calc.com/questions/circumference-of-pipe-diameter-3090mm

**Height of a triangle, the Pythagorean theorem!**

**Heron's formula to find the area of a triangle:**

**Volume of a sphere:**

**Word problems:**

• Hay bales (cylinder):

• Wagon wheels (circumference of a circle):

http://web2.0calc.com/questions/neeeed-help-on-this

$$Statistics\;and\;Probability$$

**Z scores:**

**Permutations where some objects are not unique:**

http://web2.0calc.com/questions/permutations_2

$$Set\;Theory:$$

**Introductory set theory:**

**Verifying the identity**

http://web2.0calc.com/questions/verify-the-identity-cot-theta-sec-theta-csc-theta

**Why is Sinθ approximately equal to θ for very small values of θ **

http://web2.0calc.com/questions/why-is-sin-of-theta-appromately-equal-to-theta

**How do you choose the correct trigonometric ratio (sin, cos or tan) to use?**

**Finding an angle on a right sided triangle:**

http://web2.0calc.com/questions/i-need-help-finding-the-angle-of-a-right-sided-triangle#rr2

**Unusual trig. equation (solve for θ**)

http://web2.0calc.com/questions/sin-3-cos-26-solve-for

**Changing radians to degrees:**

http://web2.0calc.com/questions/how-do-turn-radians-to-degrees

**Bearings and vectors:**

**Velocities - Looks like a great answer from Alan:**

**Light rays!**

**Some more trig. questions:**

http://web2.0calc.com/questions/8-sec2-x-4-tan2-x-12-0

http://web2.0calc.com/questions/3cosx-4sinx-1

**High level Trig:**

**University level Trigonometry:**

http://web2.0calc.com/questions/how-to-know-when-the-function-is-continuous

**Unusual Calculus/Cordinate geometry question:**

http://web2.0calc.com/questions/find-the-most-left-and-right-tangent

**Advanced calculus (thanks to Alan)**

$$Commercial\;Mathematics$$

**Difficult:**

• Compare Renting to Buying - Annuities

http://web2.0calc.com/questions/need-done-if-possible

**Forces explained by Alan**

http://web2.0calc.com/questions/finding-friction-coefficient-from-kinetic-energy

http://web2.0calc.com/questions/2d-forces-equation#r0

**Vectors:**

• Vector forces:

http://web2.0calc.com/questions/collinear-resolving-angles-of-a-parallelogram

• Converting to vector units:

http://web2.0calc.com/questions/how-to-turn-into-vector-units

• Magnitude of vector forces:

http://web2.0calc.com/questions/u-6i-j-and-v-10i-j-find-the-manitude-of-u-v

• Another vector problem:

**Distance/displacement:**

http://web2.0calc.com/questions/total-distance

**Misc. physics problems:**

http://web2.0calc.com/questions/nbsp_3

$$Puzzles:$$

**Some thinking puzzle problems:**

NinjaDevo Jul 30, 2014

#2**+3 **

NinjaDevo, can I help you with the design and update of this please? Melody said that it was fine.

DragonSlayer554 Aug 30, 2014

#2**+3 **

Best Answer

NinjaDevo, can I help you with the design and update of this please? Melody said that it was fine.

DragonSlayer554 Aug 30, 2014