In trigonometry, it is important to know the trig ratios to help solve certain problems dealing with the matters of angles, equations, degrees, unit circle, etc. There are six trig ratios.
-Co-functions are trig ratios that are the inverses of SOH CAH TOA.
-It is important to know the special triangle relationships with the degrees and the lengths to help us.
-It is better to draw these triangles, not just to memorize the degrees and lengths because memorization does not help in the long run.
-A 45-45-90 triangle has 1:1:√2 in terms of length.
-A 30-60-90 triangle has 1:√3:2 in terms of length.
If f(x)=sin^2x+tan(x)-2, find the value of f(π/4).
1. Substitute x for π/4.
2. Convert π/4 into degrees.
-Remember, in trig, π is 180 degrees.
3. If we know that sin(45) is the square root of 2 over 2, then squaring it would be 1/2.
(√2 /2)^2= (√4 /4)= 2/4= 1/2
4. Since tan theta is opposite leg over adjacent leg, and this right triangle is a right isosceles triangle, then tan(45)= 1.
5. Plug in the answers for sin^2(45) and tan(45).
1/2 + 1 -2= 3/2-2= 3/2-4/2= -1/2
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|Hello. I am Kisung Yoon, and I am a senior in high school. I am currently in the ARISTA Honor Society, and I have tutored my fellow students from my school in Algebra I, Algebra 2, Global History, US History, and Biology. Not only that, I also tutored my younger sisters on the standardized tests mai...|