Sunday, November 1, 2009

Yeah so I'm diggin' this trigonometry stuff. I think I really am picking up this stuff a lot better than the stuff we were learning the first quarter. One thing this week that I learned was Right Triangles. When I saw this I was surprised that I already knew how to do it. I learned it in Geometry last year. I even remembered SOHCAHTOA

Notes:
hypotenuse opposite right angle
A=1/2bh
SOHCAHTOA

A right triangle has an angle of 32 degrees. The adjacent leg is 5. Find the hypotenuse.

Answer=cos32=5/x
xcos32=5
x=5/cos5 or 5/5.896

The only thing that I'm still having trouble with is the word problems with the arc length and the planets and stuff.

3 comments:

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  2. Sector of a Circle (word problems):

    1. s = rθ

    2. k = θ/2 r^2

    (**Note: r = radius, θ = angle, s= arc length, & k = area of sector)

    Example:

    Find the length of the arc of a circle with radius 4 cm and central angle 5.1 radians.

    s = rθ

    = 4 × 5.1

    = 20.4 cm

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  3. The only thing that is different for word problems is that you have to decipher various names for the same meaning.
    In other words you have to know what other words will appear in a word problem that will mean radius, area, arc length, and angle.

    I cant give you all thr words that will appear but some of them include

    distance- radius
    diameter- radius
    apparent size- Theta

    for the word problem you just have to use common sense and context clues to help you decipher how to set up the problem.

    dont forget to draw your picture

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