So my math teacher, who is a Columbia finance graduate, told us he had a difficult math problem, that he believes would be a good SAT question. I tried for a while, but got nowhere close to the answer...which doesn't really mean anything because I'm awful at math.
Anyway, I normally wouldn't care, but I'm curious as to how to do this now, especially considering the SAT is this Saturday.
In the equation y= a sin(bx+c)+d
a=2.33
b=0.57
c=2.57
d=14.98
Find a cosine model for these values of sine
In other words, rewrite the equation in terms of cosine as opposed to sine.
Can anyone tell me how to do this, or give me an explanation? I doubt there will be much trig on the SAT, but I would like to know.
Thank you for your time!
Anyway, I normally wouldn't care, but I'm curious as to how to do this now, especially considering the SAT is this Saturday.
In the equation y= a sin(bx+c)+d
a=2.33
b=0.57
c=2.57
d=14.98
Find a cosine model for these values of sine
In other words, rewrite the equation in terms of cosine as opposed to sine.
Can anyone tell me how to do this, or give me an explanation? I doubt there will be much trig on the SAT, but I would like to know.
Thank you for your time!
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Remember that sin(x) = cos ((pi/2)-x) = cos (1.57-x)
y = 2.33 sin (0.57x + 2.57) + 14.98
= 2.33 cos (1.57 - (0.57x + 2.57)) + 14.98
= 2.33 cos (1.57 - 0.57x - 2.57) + 14.98
= 2.33 cos (-1 - 0.57x) + 14.98
= 2.33 cos (-0.57x -1) + 14.98
y = 2.33 sin (0.57x + 2.57) + 14.98
= 2.33 cos (1.57 - (0.57x + 2.57)) + 14.98
= 2.33 cos (1.57 - 0.57x - 2.57) + 14.98
= 2.33 cos (-1 - 0.57x) + 14.98
= 2.33 cos (-0.57x -1) + 14.98
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Hmmmm well my personal solution to this would be to do a lot of guess and checking. you would have to find a sine, cosine, tangent chart that has all of the values on it. so you would need to find a replacement for sin, and then compensate for lost values in the other values. So find that sin of 2.33 equals cosine of blank. and you would only need to find blank.