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Sunday, April 20, 2014

BQ#4 Unit T: Tan and Cot

Why is a "normal" tangent graph uphill, but a "normal cotangent graph is downhill? Use unit circle ratios to explain.

We know that our Tangent value is sin/cos or y/x. Our cotangent value is x/y or cos/sin. In order to for tan and cot to go their directions we must have our asymptotes in which for tan the x value has to be 0 while for cot our y must be 0. Tangent is 0 at the degrees of 90 and 270 because we take our coordinates of our quadrant angles. 90 degrees has a coordinate of (0,1) and 270 has a point of (0,-1). Once we plug this into our equation for both we get 1/0 and -1/0 which is our asymptote. These degrees also have radians in which 90 is pi/2 and 270 is 3pi/2. These serve as our asymptotes on our graph and is represented by a dotted line. The same thing applies to cotangent in which our value is x/y in which the degrees of 0 and 180 are our asymptotes. Plugging in our values we get 1/0 and -1/0. 0 has no asymptote on the plane while 180 lies on pi.


 




 



 
 
  By looking at our graph our asymptote for tan is placed at pi/2 and 3pi/2. These serve us as our walls which tan goes upwards. Tan also goes upward between 0 and pi/2. Cot goes downhill from its first asymptote  at zero. Cot also goes down at 180 which lies on pi.

Friday, April 18, 2014

Bq#3 Unit T: Relating graphs

How do the graphs of sine and cosine relate to each of the others? Emphasize asymptotes in your response.

A)Tangent



  Sin and cos are related to tan by looking at our trig values. Since Tan=Sin/cos or y/x By looking at our value of cosine it never touches our origin which is zero because it would cause the value to become an asymptote and become undefined. However our tan graph is going by certain amounts in which our asymptotes can act like a wall which can guide and lead the tan graph to go to that certain amount. Cosine never intersects with any of the other graphs.


 B) Cotangent






 





Cotangent has the value of cos/sin or x/y. We can see that sin goes from 0 and touches every one value of pi going to pi 2pi 3pi etc. We can see our cot  starts from the positive and transcends into negative within 0 and pi and continues which is our wall that restrains the graph and keeps it contained. Tan and cot are mirrors of the direction of the graph going up or down.
 
C) Secant

 








Secant has the value of r/x or r/cos. When cos is 0 it lies on pi/2 3pi/2 and 5pi/2. In these areas sec is split by parabolas and are split by the asymptotes into their own sections. Starting by going up then down and repeats the pattern of the direction of sec. Sin and cos act as a measurement between the graphs of secant.
 
D) Cosecant








 


Cosecant has the value of r/y or r/sin. The asymptotes lie on every pi such as 2pi 3pi etcwhich results in seperate graphs according to csc. Sin is 0 on the values of pi which is 1/0 which is an asymptote because its undefined. The pattern repeats of up and down.

Thursday, April 17, 2014

Bq#5 Unit T: 6 Trig Graphs

Why do sine and cosine NOT have asymptotes, but the other four trig graphs do? Use the unit circle ratios to explain.
     
        Sin and cosine don't have asymptotes simply by the reason of that their circle ratios are composed of having a denominator of r which is equal to one. Sin has a circle ratio is y/r and cosine has a value of x/r. Referring back to our unit circle, r has a value of one, so therefore whatever the value of x and y will be that value because the denominator is automatically one. In order to obtain an asymptote, the value must be undefined in which leads to having zero on the bottom which creates our asymptote. Other trig functions are able to have asymptotes because of their natural unit circle ratios.  Csc is r/y in which y can equal to 0 with the 90 degree angle which leads to 1/0 and is an asymptote. Secant is r/x in which you can use 270 to get the value of 1/0 which results in undefined.  Tangent and cotangent are the same in that you can mix up the values, as long as you have 0 on the bottom you can achieve an asymptote since dividing by 0 is undefined.

Wednesday, April 16, 2014

BQ#2 Unit T Unit Circle Introductions

How do the trig graphs relate to the Unit Circle?
a. Period? Why is the period for sine and cosine 2pi, whereas the period for tangent and cotangent is pi?
          Trig graphs relate to a Unit circle in that it contains quadrants from the unit circle and can be created with the use of a computer cable.
















Using all students take calculus Sin is positive in the first and second quadrant while sin is negative in the third and fourth quadrant. For cosine the first quadrant is positive, the second is negative and then it repeats itself by being negative then positive in the third and fourth quadrant. Tangent and Cotangent is positive, negative, positive and then negative. Our unit circle is also consistent of having quadrant angles split by 4 sections on the axis. For sine the first quadrant is to pi/2 then to the other half becomes pi. which is half of the unit circle, going into the 270 quadrant angle is 3pi/4 and completing at 360 is 2pi. Here if you look at the picture the quadrants are divided along the line by the quadrants and their values according to the trig function. When you look at the lines going up and down on the line, this is based on our sin value of the quadrants both being positive and then negative in the 3rd and 4th quadrant. We can see this by my lines indicated on the line, after the second one there's a "valley" in which the sin values are negative so they go below. Sin and cosine are 2pi because they don't have a complete pattern like tan and cot. Sin is positive positive then negative negative, so it has to go through a whole go around the unit circle, same thing applies to cosine in which it doesn't complete its pattern. While tan and cot complete its pattern of being positive negative then positive negative.

b) Amplitude?-How does the fact that sin and cosine have amplitudes of one (and the other trig functions don't have amplitudes) relate to what we know about our unit circle?
Sin and cosine have restrictions on their values as -1<x<1 Since we know the unit circle has an r value of one hence our trig values for sin is y/r and x/r belongs to cos. If we get x or y values greater then -1 or less than -1 we get error and it doesn't work, meanwhile the other trig functions you can mix and match the values of the unit circle.

Thursday, April 3, 2014

Reflection:#1: Unit Q verifying trig functions

1.What does it actually mean to verify a trig identity?
To verify a trig identity is to start off with what you're given and turn it around and adjust the given values to make it equal to what the trig identity is giving us. With verifying we can use our reciprocal trig values or sub in with identities. We're open to numerous different ways to verify the different identities.


2.What tips and tricks have you found helpful?
Tips and tricks I've used are basically try every single way possible and test things that you've never done before. Other tips include just knowing your identities and what values they are and make sure to not mistake for subtraction signs and addition signs.

3.Explain your thought process and steps you take in verifying a trig identity.  Do not use a specific example, but speak in general terms of what you would do no matter what they give you.
My thought process just include depending on the concept. For concept 4 I wonder if I'm able to factor out anything such as a trig function or if I'm able to use the zero product property. I also look for any functions I can convert and see if it cancels with anything or it can add too my current problem. I also check if I should square both sides and check for extraneous solutions. For problems like concept 5 I include the same thought process, except i put the right side as a no no touch boundary and only convert the left side if possible.