There weren't that many trig questions on my test. However, in term of DAT, I don't think that they will ever ask anything above and beyond.
This is what I think can come up:
sin=opp/hyp csc=1/sin
cos=adj/hyp. sec= 1/cos
Then for tan and cot, just remember that tan=sin/cos and
cot=cos/sin
Then, csc has 2 c in it, and it doesn't need any more c on the other side, so, csc=1/sin. And of course, sec should pair with cos
You guys should also know all the special right triangles.. Practice to find sin and cos of the two acute angles.
For the values of the sin, cos, tan, cot. Follow those easy steps:
1. Write the angle in degree :
0 30 45 60 90
2. Write 0 to 4 under those number:
0 1 2 3 4
3. Square root these number and divide it by two:
sin 0 1/2 sqrt2/2 sqrt3/2 1
4. For cosine, it's the opposite of sine. Do a bow tie cross between 0 and 90 degree, 30 and 60 degree. cos and sin of 45 degrees are the same.
cos 1 sqrt3/2 sqrt2/2 1/2 0
5. Then, tan=sin/cos.
tan 0 sqrt3/3 1 sqrt3 undefined
6. Again, cot is the opposite of tan for 0 and 90 degree, 30 and 60 degree. cot and tan of 45 degree are also the same.
cot undefined sqrt3 1 sqrt3/3 0
By now, you should have a table with all the values of sin, cos, tan and cot for 0, 30, 60, 90
You guys should always write this table down at your tutorial section and keep this scratch paper to use in the math section.
There will be an occasion that you need to know tan60=? So, all you need to do is to glance at the table, no sweat, right?
Another thing I find helpful when I studied the DAT with Topscore, there were 1 trig question asked about the sign of cot.
You should always think of the circle.
With radius=1 and center at O. The y-axis is sin, x-axis is cos.
For example, if the angle is 290 degree, is cot<0 or cot>0?
290 degree angle will lie in the fourth quadrant. So, sin value will be negative and cos will be positive. Therefore, cot290<0
And remember, in the worst case scenario that you have a thunder sent trig question, don' t panic. Draw the trig circle out. Write sin and cos axis, Write -1 and 1 on the two sides of the circle. Draw your angle and analyze the question. But I don't think it will ever happen on any standardized test.
Finally, remember STATISTICS? I have this shortcut equation:
1. To find the variance:
(Sum of squares of sample measurement)- (Sum
of sample measurement)square/n
s-square=-----------------------------------------------------------
n
So, it means that first of all, you square all of the numbers in the sample and add them up.
Then, you add all of those numbers, square them up and divide by n.
Substract the first value to the second value, you will get the nominator.
Lastly, divide the nominator to the number of numbers you have in the sample, this value is denoted as n in the equation.
You get the variance now.
2. Standard deviation is s, which is the square root of variance.
3. Mode: number that comes up the most.
4. Median: the middle number in order.
Kaplan CD has a very good problem regarding the Variance, standard deviation and average. Check them out before taking the test. They are easy questions and can be answered in a few seconds.
Happy studying, and if you guys have any more questions, please feel free to post. I'll try my best if I could. And good luck to all of you.
T
