Trig equations 1 (no b or h involved): you can see some directly from blogs, like Cass’s post and Tanyse’s post and here are those that came in via the checklists:
Firstly, we must make equation equal to zero since we are looking for the x’s which are the zeroes! After simplifying the equation algebraically (if needed), we work our memory into remembering which of The Big Seventeen is equal to either the cos or sin of an angle. After doing so, we write down our findings and make sure to include that all their coterminal angles are also part of the answer! 🙂
well i would start off with having remembering that cos =x sin=y when dealing with ordered pairs so if u know all the order pairs u can easily solve em. also all the b17 in radians. also there can be to possible answers!
well that it d(^-^)b
do the algerbra isolate cos or sin x
look at big 17 and find the cos(x) or sin(y) values that match with value found (could be 2)
add all cotermial angles +-2pin,n=N (plug n with a number to slove for a cotermial angle
and there we go
first you have to find the angle in radians, there can be more than one angle and if there is you have to use them all. Next you have to add it to 2pi and you get a coterminal number. THen you have to times the next whole number to 2pi and continue or you can just add the mulitple it increased by to make you life easyer
I solve them by isolation the x. The I find the angle that corresponds to an angle on the unit circle. Then I add 2 pi n.
How will we know if there is a solution or not? How do we know if there is one of to values for the same point?
This you have to find what angles have the same y or x values. There can be more than one. Then you look for the coterminal values
How to solve them: When looking at the equation, we must first start with the number that has a positive or negative sign, we put it on the opposite side. Then we being the number where there it is multiplying on the other side and then we get an a fraction.
I isolated the x of cos or sin then found the coordonants then + 2 pi n
When you have the equation, frst step is to isolate the cosx or sinx. Then you need to remember the trig point on the big17 that goes with it. The siin(y) and cosss(x) trick are very useful.
My question is, how are we going to solve the equation when its not a point we learned on the big17?
The way to solve them is isolate the cos or the sin and the x. Then find the point on the unit circle and find the value for that point
Depending on what is given, sometimes you only have to look at the ‘Big Seventeen’ chart and you have your answer right away. But when it gets more difficult, the most important aspect is that you make sure to analyze the formula/equation given as closely as possible.
First you need to iscolate the sin(X). so depending on what variables are in the equasion, have to use different options to do so. once you have sin x = .. lets say 1. we convert it to radians. at what point is the height 1? at pi/2 radians. that is our answer, and this is a zero of the function. to represent all the other zeroes of this function as well, we write “+/- 2piN” because the Zeros reoccur every 2 pi. if there is an h, we have to add it to the 2pi, because the cycle wouldnt be reoccuring at every 2 pi any more. My question is : are we goin goin g to use this method to solve for other y values in the function. But i guess it is probably quite obvious that that is what we are going to do.
1. algebra (isolate cosx or sinx)
2. Remember or check reference (to find which angle fits with the result of coordinate x or y)
3. write the angle(s) and their coterminals (or the formula which means the coterminals )
XE( x= angle in radians + 2 pi n, or x = other angle (if there is one) in radians + 2 pi n, XE N (whole numbers))