Saturday, February 14, 2015

If x is an angle in standard position with point A(-3 , 4) on the terminal side, then sec(x) =

We will draw a line between the point (-3, 4) and the
origin point.


Then angle x located between the line and the
x-axis.


Then, we hace formed a right angle triangle where
the base = 3, the height = 4 .


Now we will calculate the
length of the line which is the hypotenuse.


==> The
hypotenuse = sqrt(3^2 + 4^2 ) = sqrt25 = 5


Now we will
determine sec(x).


We know that sec(x) =
1/cos(x)


But cos(x) = adjacent /
hypotenuse.


==> cos(x) =
3/5


But the angle is in the 4th
quadrant.


then cos(x) =
-3/5


==> sec(x) =
-5/3

No comments:

Post a Comment

Calculate tan(x-y), if sin x=1/2 and sin y=1/3. 0

We'll write the formula of the tangent of difference of 2 angles. tan (x-y) = (tan x - tan y)/(1 + tan x*tan y) ...