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#1051
Quote of the Day - 2
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New #1052
My cousins gay, he went to London only to find out that Big Ben was a clock.
Rodney Dangerfield
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New #1053
You have noticed that everything an Indian does in a circle,
and that is because the Power of the World always works in circles,
and everything and everything tries to be round.
In the old days all our power came to us from the sacred hoop
of the nation and so long as the hoop was unbroken the people
flourished. The flowering tree was the living center of the hoop,
and the circle of the four quarters nourished it. The east gave peace
and light, the south gave warmth, the west gave rain and the north
with its cold and mighty wind gave strength and endurance. This
knowledge came to us from the outer world with our religion.
Everything the power of the world does is done in a circle.
The sky is round and I have heard that the earth is round like a ball
and so are all the stars. The wind, in its greatest power, whirls.
Birds make their nests in circles, for theirs is the same religion as ours.
The sun comes forth and goes down again in a circle. The moon
does the same and both are round. Even the seasons form a great
circle in their changing and always come back again to where they were.
The life of a man is a circle from childhood to childhood, and so it is
in everything where power moves. Our teepees were round like the
nests of birds, and these were always set in a circle, the nation's hoop,
a nest of many nests, where the Great Spirit meant for us to hatch our children.
Black Elk, Holy Man of the Oglala Sioux 1863-1950
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New #1054
Ojibwe sayingSometimes I go about in pity for myself, and all the while a great wind carries me across the sky.
(and tony soprano)
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New #1056
"If toast always lands butter-side down, and cats always land on their feet, what happens if you strap toast on the back of a cat and drop it?"
~ Stephen Wright
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New #1058
Funny you should mention that.
Murphy's law application for antigravitatory cats - Uncyclopedia, the content-free encyclopedia
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New #1059
Fantastic link, Devux.
When I reached the formula for Sine & Cosine involvement, I gave up - blew my mind all those years ago when I was at school....
.... Sine Rule and Cosine Rule
Sine and cosine can be used on any triangle, not just right-angled triangles. But as there is no right angle, there is no hypotenuse, so different formulae are needed
Sine RuleNotice that the small letters, for the lengths of the sides, are opposite to the corresponding capital letters for the angles.
So for this triangle…So, if an angle and the length of its opposite side is known, then the other angles and sides can be worked out, using just one other length or angle. But be careful when the triangle is obtuse angled, because, for example, sin50 = sin130, that is sin x = sin (180-x)
You are given angles A and C and side c, so use
B=180-(60+45)=75 and now
That just leaves the triangle where opposite sides/angles are not given;
Having worked this out, you now have side a, opposite to angle A and so the sine rule can be used to work out the other angles.
Here the Cosine rule is needed.
The cosine rule is also used when the three sides are given.
This method can be used again to find another angle, or the sine rule, which is a bit shorter, can be used.
Using these methods, any triangle can be ‘solved’. That is all of the angles and sides of a triangle can be worked out, if enough information is given to start with.
Of course the sine and cosine rules can be used on right angled triangles, but it easier to use the usual ratios for right angled triangles.
Try out the methods on this question.
Use the cosine rule to work out length aThen use the sine rule to work out angle B
Finally use C=180-(A+B) to work out C
answers
Return to Everything You Ever Wanted to know about Triangles
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