What is sin A when the opposite side is 3 and the hypotenuse is 5?
Trigonometry begins with one idea: a ratio of two sides. Label the sides for your chosen angle, and the ratio is mechanical.
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1 lesson for “Trigonometric ratios”
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Which coefficient becomes your ratio?
Coefficients are ratios. Three moles of O2 in the hydrogen reaction make twice as much water. Learn to read the recipe.
Try this lessonWhich number goes first in a ratio?
Nia counted 10 bus riders and 6 walkers and wrote the ratio of walkers to bus riders as 5:3. She answered a different question than the one asked.
Try this lessonIn a 30-60-90 triangle, what is the hypotenuse if the short leg is 5?
A 30-60-90 triangle has fixed ratios between its sides. Know one side and the other two follow without any trigonometry.
Try this lessonWhat is the 5th term of 2, 6, 18, ...?
In a geometric sequence, each term multiplies the last by the same ratio. That ratio is the engine of the whole sequence.
Try this lessonWhere do the cross products come from?
Tess solved 6/10 = 30/x by computing 6 * 30 / 10 and got 18. The cross products were paired wrong.
Try this lessonWhich reactant runs out first?
3.0 mol of O2 and 4.0 mol of H2: which runs out first? The ratio decides, not the smaller number.
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