Thursday

October 23, 2014

October 23, 2014

Posted by **nadia** on Saturday, November 10, 2012 at 6:13pm.

a) sin 13pi/6 b) cos 11pi/8

c) tan 7pi/4

- Advance fuctions -
**Reiny**, Saturday, November 10, 2012 at 6:40pma) sin(13π/6)

= sin(2π + π/6)

so we are in quadrant I with an angle of sin π/6

sin π/6 = 1/2

cos(11π/6)

= cos(2π-π/6) .... ( think: 330° = 360° - 30°)

so we are in quad IV and in IV the cosine is positive

= cos π/6 = √3/2

c) tan 7π/4

= tan (2π - π/4) ------ in IV where the tangent is negative

= -tan π/4 = -1

You can and should check your answers with a calculator.

**Answer this Question**

**Related Questions**

Advance fuctions - write and that is equivalent to each of the following ...

Math - 3. find the four angles that define the fourth root of z1=1+ sqrt3*i z...

Math - How does the related acute angle help to determine the trigonometric ...

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

Precalculus check answers help! - 1. Which expression is equivalent to cos ...

Trigonometry - Checking my work - Find the sum of the three smallest positive ...

math - 1. express tan 11pi/6 in terms of a positive acute angle 2. solve for x...

math - Use the exact values of the sin, cos and tan of pi/3 and pi/6, and the ...

Trigonometry - If cos(a)=1/2 and sin(b)=2/3, find sin(a+b), if 1) Both angles ...

math - Use the exact values of the sin, cos and tan of pi/3 and pi/6, and the ...