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Further trigonometry- compound identities.

For the most part this question makes sense. I’m just not quite certain on when it asks the max and smallest value.

Question 6.
So, writing as a single trig function is straightforward

Given the compound identity, use its identity.

So, first part for:
a.sin(x+π/4)

If I take this answer and imagine
on the sin x graph, it’s max x value must be π/4. I’m not sure if I’m understanding the question correctly
Original post by KingRich
For the most part this question makes sense. I’m just not quite certain on when it asks the max and smallest value.

Question 6.
So, writing as a single trig function is straightforward

Given the compound identity, use its identity.

So, first part for:
a.sin(x+π/4)

If I take this answer and imagine
on the sin x graph, it’s max x value must be π/4. I’m not sure if I’m understanding the question correctly

It would help to see the question.
But if a is positive, youre correct that the first max value would be at x=pi/4.
Reply 2
Original post by mqb2766
It would help to see the question.
But if a is positive, youre correct that the first max value would be at x=pi/4.


Oops forgot to attach.

FAE7F757-0E83-48FA-BD59-096D25D4CED2.jpeg
Original post by KingRich
Oops forgot to attach.

FAE7F757-0E83-48FA-BD59-096D25D4CED2.jpeg

So looks like youre good?
Reply 4
Original post by mqb2766
So looks like youre good?

I believe I’m applying the transformation based on the single trigonometric value that I find?
Hence, x moves left by 45degress which is the reason for the new max value being at 45 degrees. For the smallest possible value of x is what I’m not sure about?
Reply 5
Original post by mqb2766
So looks like youre good?

Lol. What am I saying right now. Max value is as I said and the x=π/4 and y=1. What the heck man.
(edited 1 year ago)
Original post by KingRich
Lol. What am I saying right now. Max value is as I said and the x=π/4 and y=1. What the heck man.


Agreed. You can think of it as transformations, but the easiest thing will be simply the sub the "obvious" value in to get sin(pi/2).

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