Sunday

September 21, 2014

September 21, 2014

Posted by **kate** on Monday, January 25, 2010 at 3:47pm.

(a) cos 143 degrees

(b) tan 192 degrees

- pre calc -
**Reiny**, Monday, January 25, 2010 at 5:55pmI do these with the following steps:

cos 143

- which quadrant is it in? --- 2nd

- by CAST rule, what sign is the cosine in the 2nd? --- negative

- how far from 143º to the x-axis ? --- 37

so cos 143 = - cos 37

do the other one the same way.

**Answer this Question**

**Related Questions**

trig - How do you express in terms of angles less than 90 degrees? sin 120 ...

Trigonometry - Please review and tell me if i did something wrong. Find the ...

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

Math - How do you express in terms of angles less than 90 degrees? sin 120 ...

Trigonometry - use the appropriate trig identity (sum and difference, half angle...

trig (pre-cal class) - Suppose è is an acute angle of a right triangle. For this...

maths - write each of the following as trigonometric ratios of acute angles. (a)...

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

trig - Give the measure of the acute angle with each given value to the nearest ...

trig - Determine if the value of each trig function is positive, negative, zero...