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Example Questions
Example Question #4 : How To Find The Period Of The Cosine
A function with period will repeat its solutions in intervals of length .
What is the period of the function ?
For a trigonometric function , the period is equal to . So, for , .
Example Question #41 : Cosine
A function with period will repeat its solutions in intervals of length .
What is the period of the function ?
For a trigonometric function , the period is equal to . So, for , .
Example Question #141 : Trigonometry
A function with period will repeat its solutions in intervals of length .
What is the period of the function ?
For a trigonometric function , the period is equal to . So, for , .
Example Question #1 : How To Find The Range Of The Cosine
Simplify (cosΘ – sinΘ)2
1 + cos2Θ
1 – sin2Θ
cos2Θ – 1
sin2Θ – 1
1 + sin2Θ
1 – sin2Θ
Multiply out the quadratic equation to get cosΘ2 – 2cosΘsinΘ + sinΘ2
Then use the following trig identities to simplify the expression:
sin2Θ = 2sinΘcosΘ
sinΘ2 + cosΘ2 = 1
1 – sin2Θ is the correct answer for (cosΘ – sinΘ)2
1 + sin2Θ is the correct answer for (cosΘ + sinΘ)2
Example Question #1 : How To Find The Range Of The Cosine
Which of the following represents a cosine function with a range of to ?
The range of a cosine wave is altered by the coefficient placed in front of the base equation. So, if you have , this means that the highest point on the wave will be at and the lowest at ; however, if you then begin to shift the equation vertically by adding values, as in, , then you need to account for said shift. This would make the minimum value to be and the maximum value to be .
For our question, the range of values covers . This range is accomplished by having either or as your coefficient. ( merely flips the equation over the -axis. The range "spread" remains the same.) We need to make the upper value to be instead of . To do this, you will need to subtract , or , from . This requires an downward shift of . An example of performing a shift like this is:
Among the possible answers, the one that works is:
The parameter does not matter, as it only alters the frequency of the function.
Example Question #1 : How To Find The Range Of The Cosine
Which of the following represents a cosine function with a range from to ?
The range of a cosine wave is altered by the coefficient placed in front of the base equation. So, if you have , this means that the highest point on the wave will be at and the lowest at ; however, if you then begin to shift the equation vertically by adding values, as in, , then you need to account for said shift. This would make the minimum value to be and the maximum value to be .
For our question, the range of values covers . This range is accomplished by having either or as your coefficient. ( merely flips the equation over the -axis. The range "spread" remains the same.) We need to make the upper value to be instead of . This requires an upward shift of . An example of performing a shift like this is:
Among the possible answers, the one that works is:
Example Question #4 : How To Find The Range Of The Cosine
What is the range of the trigonometric function defined by ?
The range of a sine or cosine function spans from the negative amplitude to the positive amplitutde. The amplutide is given by in the equation . Thus the range for our function is
Example Question #1 : How To Find The Range Of The Cosine
What is the range of the given trigonometric equation:
For the sine and cosine funcitons, the range is equal to the negative amplitude to the positive amplitude.
The amplitude is found by taking from the general equation:
.
We see in our equation that
(when no coefficient is written, it is a 1).
Thus we get that the amplitude is
Example Question #6 : How To Find The Range Of The Cosine
What is the range of the function ?
There is no valid range for this equation.
The range of the function represents the spread of possible answers you can get for , given all values of . In this case, the ordinary range for a cosine function is , since the largest value that cosine can solve to is (for a cosine of or a multiple of one of those values), and the smallest value cosine can solve to is (for a cosine of or a multiple of one of those values).
However, in this case our final answer is increased by after the cosine is applied to . This results in a final range of to (or, in other words, to , plus ).
So, our final range is .
Example Question #7 : How To Find The Range Of The Cosine
What is the range of the function ?
There is no range that fits this equation.
The range of the function represents the spread of possible answers you can get for , given all values of . In this case, the ordinary range for a cosine function is , since the largest value that cosine can solve to is (for a cosine of or a multiple of one of those values), and the smallest value cosine can solve to is (for a cosine of or a multiple of one of those values).
However, in this case our final answer is multiplied by -3 after the cosine is applied to . This results in a final range of to (or, in other words, to , multiplied by ).
So, our final range is .
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