Expert: Sherman D. - 12/11/2007

Question
QUESTION: Derive the identity
     Cot2 A + 1 = csc2  A    



ANSWER: cot(A)^2 + 1
(cos(A)/sin(A))^2 + 1
(cos(A)^2 + sin(A)^2)/sin(A)^2
1/sin(A)^2
csc(A)^2

more info found at www.math.com/tables/trig/identities.htm

---------- FOLLOW-UP ----------

QUESTION: can you Express the following in degrees,minutes,and seconds
a.4          c.    π          e.  – 1.4
         6

b.0.23         d.   3π         f. 9.6
         2



ANSWER: by theses do you mean

a.) 4
b.) .23
c.) pi/6
d.) 3pi
e.) -1.4
f.) 9.6

anytime you make a fraction, just either put it like (a/b) or a/b depending on your problem.


---------- FOLLOW-UP ----------

QUESTION: a.) 4
b.) .23
c.) pi/6
d.) 3pi
e.) -1.4
f.) 9.6
can you Express the following in degrees,minutes,and seconds

Answer
a.)
4 = 4°

b.)
.23 * 60 = 13.8
.8 * 60 = 48
.23 = 0°13'48"

c.)
pi/6 or 30°
About all you do is plug in 180 for pi, then divide by 6

d.)
3pi = 2pi + pi = 360 + 180 = either 540 or 180° or 0°
Its basically a a straight line.

e.)
-1.4
.4 * 60 = 24
-1°24'0" or 358°36'00" when you add that to 360

f.)
9.6 = 9°36'00"

more info found at http://geography.about.com/library/howto/htdegrees.htm