formula d

…the book Pidge uses to study in the flashback confuses me a lot. First of all, the two pages are exactly the same:

Second of all, the math is wrong?? ???? 

₀∫ 1cos(x) dx = sin - 2x      ?? ?!??!? NONONONONO

₀∫ 1cos(x) dx = ₀[sin(x)] = sin(2π) - sin(0) = 0 - 0 = 0      yes,,,

And then this thing:

WP = √(sin²(θ))      = (sin²(θ))½ = sin(θ) 

Which. What the fuck. Assuming we’re looking at physics equations here and that W = work and P = power, the formula should look like this: P = W/t. Simple. The angle is throwing me for a loop, if W & P stand for what they usually stand for it doesn’t matter.

As for the sketch at the end, I’m not even sure what it’s supposed to show…

Me @ dreamworks:

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please no character hate or that God Damn Meme™, thank you

Formulas to Remember for the Math Section of SAT

Algebra

Percents:

Percent Change= Change/Original × 100

Part = Percent /100 × Whole

Examples:

75% of 300 is what?

Solve x = (75/100) × 300 to get 225

45 is what percent of 60?

Solve 45 = (x/100) × 60 to get 75%

Example: 30 is 20% of what?

Solve 30 = (20/100) × x to get 150

Average Speed = total distance/total time

Distance =rate × time

 

FOIL: (x + a)(x + b) = x ^2 + (b + a)x + ab

Difference of Squares:

a)     a ^2 − b ^2 = (a + b)(a − b)

b)    a ^2 + 2ab + b^ 2 = (a + b)(a + b)

c)     a ^2 − 2ab + b^ 2 = (a − b)(a − b)

Distance Formula:  SQRT (x2 − x1) ^2 + (y2 − y1) ^2

Mid-point of the segment AB: x1 + x2 /2, y1 + y2/2

Slope of the line: y2 − y1 / x2 − x1 = rise run


Geometry

Opposite Angles are equal, so a+b and 180 degrees.

All the “a’s” are equal and all the “b’s” are equal. Any “a” plus any “b” equals 180 degrees.

 

Right Triangle Formulas***

Triangle area= ½*b*h ***

Angles in a triangle add up to 180 degrees.***

 

Circles

Area of a Circle = πr2 ***

Circumference = 2πr ***

Full circle = 360◦ ***

Length Of Arc = (n ◦ /360◦ ) × 2πr

Area Of Sector = (n ◦ /360◦ ) × πr2

 

Total number of degrees in the interior of an n-sided polygon= (n-2) × 180 where n is the number of sides.

For example, an eight-sided polygon (or octagon) has:

(8 – 2) · 180 = 6 · 180 =  1080 degrees

 

Arithmetic

Arithmetic sequence formula: an=a1+d(n-1)

a1=first term, d =distance between the numbers, and n= term to find

Example: Find tenth term in 3,7,11….

a10=3+4(10-1)= 63


Geometric sequence formula: an=a1×r(n-1)

a1=first term, r =rate  between the numbers, and n= term to find

Example: Find 6th term in 3,6,12…

a6=3×2(6-1) = 3×2 5=3×32= 96

Functions

I was putting together a cheat sheet for studying for the math section of the SAT. Hope this helps some of you! :)

*** on the SAT given formulas, but still good to know by heart.