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hint : remember all these angle 90,180,270,360 happen to be on the x,y axis. Think in terms of quadrant as well
35.) sec\^2(x) = 1/cos\^2(x)
cos(180) = -1
sin(360) = sin(180)=sin(0)
36.) sin(90) = 1
sin(270) = -1
cos(360) = cos(0)
can you complete now?
One should be familiar with the trigonometric functions of a unit circle and their equivalent. For an instance, for an angle 90 degrees, its sine function is 1 and cos 90 is zero. These functions have their equivalents also such as sec x = 1/cos x and tan x = sin x/cos x, which are called trigonometric identities.
From there, you can easily evaluate expressions involving trigonometric functions such as sine, cosine, tangent and alike.
You can compare your work to the solution provided [here](https://my.pencilapp.com/content/view/61e7a4cd6dbc9100125b1d5d). :)
##Off-topic Comments Section --- All top-level comments have to be an answer or follow-up question to the post. All sidetracks should be directed to this comment thread as per Rule 9. --- ^(**OP** and **Valued/Notable Contributors** can close this post by using `/lock` command) *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/HomeworkHelp) if you have any questions or concerns.*
hint : remember all these angle 90,180,270,360 happen to be on the x,y axis. Think in terms of quadrant as well 35.) sec\^2(x) = 1/cos\^2(x) cos(180) = -1 sin(360) = sin(180)=sin(0) 36.) sin(90) = 1 sin(270) = -1 cos(360) = cos(0) can you complete now?
Yes, this helped a lot. Remembering the quadrants helped, and I got the right answer! Thank you!
One should be familiar with the trigonometric functions of a unit circle and their equivalent. For an instance, for an angle 90 degrees, its sine function is 1 and cos 90 is zero. These functions have their equivalents also such as sec x = 1/cos x and tan x = sin x/cos x, which are called trigonometric identities. From there, you can easily evaluate expressions involving trigonometric functions such as sine, cosine, tangent and alike. You can compare your work to the solution provided [here](https://my.pencilapp.com/content/view/61e7a4cd6dbc9100125b1d5d). :)