Tuesday

July 22, 2014

July 22, 2014

Posted by **Purplechick4** on Monday, February 6, 2012 at 9:28pm.

- Pre-Calc -
**Reiny**, Monday, February 6, 2012 at 10:00pmPerhaps you can "think" better in degrees than radians, sometimes I can.

sin(-15π/6)

= sin(-450°)

= sin(-90) , I took away one rotation

= -sin(90°) = -1

cot (-7π/6)

= cot(-210°)

= cot(150°) , 150 and -210 are coterminal

= - cot(30°) , 150 is in II and by CAST rule cotangent is negative, and 30° from the x-axis

= -1/tan 30°

= -1/(1/√3) = -√3

- Pre-Calc -
**Purplechick4**, Monday, February 6, 2012 at 10:09pmThank youu(:

**Related Questions**

math - Eliminate the parameter (What does that mean?) and write a rectangular ...

pre-calc - Can someone help me find the exact value of 4csc(3pi/4)-cot(-pi/4)? ...

trig/pre -calc - hello, i don't quite understand how to do this type of problem...

Pre-calc/Trig - If cot(a)=3 and sin(b)= (15/17) where a being alpha lies in ...

Pre-Calc : Find the Exact Value of the Expression - Find the exact value of the ...

Pre calculus - How do you work this problem? Find the exact value of sin 2u, cos...

Precalculus/Trig 6 - Find the exact value of the following trigonometric ...

pre calc - The minute hand of a clock is 7 inches long. How far does the tip ...

Pre-Calc - Find the values of the trigonometric functions of è from the ...

Algebra II - Multiple Choice (theta) means the symbol 0 with the dash in it. 1.)...