Question

can someone explain how sec(-pi/4) = sqrt2? I have never encountered a negative angle like this roflmao

Answer 1

sec(-pi/4) = 1/(cos(-pi/4)) which equals sqrt of 2

Answer 2

You just answered your question. =))

Answer 3

yeah but I don't know why or how this is looking at the unit circle

Answer 4

cosine deals with values on the x-axis, sin deals with values on the y-axis.



notice how at that angle, even though y is negative, the x value is still positive? so when you do: 1/cos( -pi/4) you will still get a positive value. since

cos (-pi/4)=cos(pi/4)= sqrt(2)/2
1/cos(-pi/4)= 2/sqrt(2)=sqrt(2)

Answer 5

thanks!

Answer 6

conjugation x_x