# Khan/khan-exercises

Fix errors with spelling and grammar. Also changed the test mode cond…

…itional to allow "127.0.0.1".

Test plan:  Try out each exercise that I have modified, while using hints.
1 parent 646d977 commit d89d39cfb7d82dd08c5721c53bbaed7f5b15b49b rhc2104 committed Jul 27, 2011
 @@ -118,10 +118,10 @@

- So, the correct answer is SOLUTION. + Thus, the correct answer is SOLUTION.

- The absolute value can not be negative. So, there is no solution. + The absolute value cannot be negative. Therefore, there is no solution.

 @@ -662,7 +662,7 @@

\color{purple}{\angle{DAK}} = 90°, - because angles formed by perpendicular lines equal to 90°. + because angles formed by perpendicular lines are equal to 90°. label( [-1.68, 2], "\\color{purple}{90°}", "above left" ); arc( [0, 2], 1.65, 90, 180, {stroke: "purple"} ); @@ -726,4 +726,4 @@ - +

 @@ -390,7 +390,7 @@ \color{purple}{\angle{BHD}} = 180° - \color{green}{\angle{BDC}} - \color{orange}{\angle{DBE}} = Tri_Z°. - This is because interior angles of a triangle add up to 180°. + This is because the interior angles of a triangle add up to 180°. // label angle BHD arc([3.2, 1.3], .75, 118, 220, { stroke: "purple" });
 @@ -98,7 +98,7 @@

This is like considering two equally sized pizzas that have been cut into DEN_1 equal slices.

-

Since both pizzas have the same number of slices, all the slice are the same size.

+

Since both pizzas have the same number of slices, all the slices are the same size.

init({ range: [ [-3, 3], [-3, 3] ], scale: 25 });
 @@ -96,7 +96,7 @@
-

You can only possibly pick a fair coin or pick an unfair coin. There is no other outcome.

+

You can only pick a fair coin or pick an unfair coin. There is no other outcome.

What chance do you have of picking an unfair coin? How about a fair coin?

 @@ -36,7 +36,7 @@ F === 0 ? null : F ]) = 0.

-

What are its center (h, k) and its radius r?

+

What is its center (h, k) and its radius r?

 @@ -22,7 +22,7 @@
D
-

To get the right numerator C, the left numerator A was multiplied by M.

+

To get the right numerator C, the left numerator A is multiplied by M.

To find the right denominator, multiply the left denominator by M as well.

B \times M = D

@@ -34,7 +34,7 @@
C
-

To get the right denominator D, the left denominator B was multiplied by M.

+

To get the right denominator D, the left denominator B is multiplied by M.

To find the right numerator, multiply the left numerator by M as well.

A \times M = C

@@ -46,7 +46,7 @@
B
-

To get the right numerator A, the left numerator C was divided by M.

+

To get the right numerator A, the left numerator C is divided by M.

To find the right denominator, divide the left denominator by M as well.

D \div M = B

@@ -58,7 +58,7 @@
A
-

To get the right denominator B, the left denominator D was divided by M.

+

To get the right denominator B, the left denominator D is divided by M.

To find the right numerator, divide the left numerator by M as well.

C \div M = A

 @@ -94,15 +94,15 @@

The function starts at its maximum value (ie, f(0)=VSCALE), so what kind of function is it?

-

The cosine function, \cos(x) starts at 1 (ie, \cos(0)=1), so f(x) must be a scaled version of the cosine function.

+

The cosine function, \cos(x), starts at 1 (ie, \cos(0)=1), so f(x) must be a scaled version of the cosine function.

The function starts at zero (ie, f(0)=0), so what kind of function is it?

-

The sine function, \sin(x) starts at 0 (ie, \sin(0)=0), so f(x) must be a scaled version of the sine function.

+

The sine function, \sin(x), starts at 0 (ie, \sin(0)=0), so f(x) must be a scaled version of the sine function.

@@ -123,14 +123,14 @@
-

The period of a normal FNS function is 2\pi, and the period we want is piFraction( PERIOD ), so we don't need to worry about scaling the function horizantally.

+

The period of a normal FNS function is 2\pi, and the period we want is piFraction( PERIOD ), so we don't need to worry about scaling the function horizontally.

The period of a normal FNS function is 2\pi, and the period we want is piFraction( PERIOD ), so we need to scale the FNS function horizontally by decFrac( PERIOD / 2 / PI ).

-

To horizontally scale \FN(x) by decFrac( PERIOD / 2 / PI ), we need to subsitute decFrac( 2 * PI / PERIOD )x in for x to get \FN(decFrac( 2 * PI / PERIOD )x).

+

To horizontally scale \FN(x) by decFrac( PERIOD / 2 / PI ), we need to substitute decFrac( 2 * PI / PERIOD )x in for x to get \FN(decFrac( 2 * PI / PERIOD )x).

 @@ -17,7 +17,7 @@ getPrime()

What is the prime factorization of NUMBER?

-

Type each prime factor separated by an x, like this: 2 x 3.

+

Type each prime factor separated by an x (as in the letter), like this: 2 x 3.

NUMBER

Let us draw a factor tree.

@@ -48,7 +48,7 @@

What is the prime factorization of NUMBER?

-

Type each prime factor separated by an x, like this: 2 x 3.

+

Type each prime factor separated by an x (as in the letter), like this: 2 x 3.

SOLUTION.join("x")

 @@ -29,7 +29,7 @@

s * s * s

-

The volume of a cube with side s is V = s^3.

+

The volume of a cube with side length s is V = s^3.

\qquad \hphantom{V} = s \cdot s \cdot s

\qquad \hphantom{V} = s * s * s

 @@ -296,7 +296,7 @@

X = \dfrac{ plus( (E*C)+Z, (-B*F)+Y ) }{ color( A*F-D*C, false ) }

-

All of these terms are divisable by GCD.

+

All of these terms are divisible by GCD.

Divide by the common factor and swap signs so the denominator isn't negative.

Divide by the common factor.

Swap signs so the denominator isn't negative.

@@ -312,4 +312,4 @@
- +
 @@ -36,7 +36,10 @@ var primes = [2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, }, // Check to see if we're in test mode - testMode = (window.location.host.indexOf("localhost") === 0 || window.location.protocol === "file:") && /\.html$/.test( window.location.pathname ), + testMode = (window.location.host.indexOf("localhost") === 0 || + window.location.host.indexOf("127.0.0.1") === 0 || + window.location.protocol === "file:") && + /\.html$/.test( window.location.pathname ), // Check to see if we're in beta mode betaMode = window.location.host.indexOf( "khan-masterslave" ) !== -1,