# use degree measure for your answers. use a calculator and round the results to one decimal place for (c) and (d)

(a) in triangle ABC, sin B = square root of 2 all over 2. What are the possible values for angle B?

my thought: since sin is positive in the first and second quadrant, I believe that it is 45 degrees and 135 degrees.

(b) in triangle DEF, cos E = square root of 2 all over 2. What are the possible values for angle E?

my thought: since cos is positive in the first and fourth quadrant, I believe that it is 45 degrees and 315 degrees. This answer, however, does not agree with book answer.

(c)In triangle GHI, sin H = 1/4. What are the possible values for angle H?

My thought: ? Book answer: 14.5 degrees or 165.5 degrees

(d) In triangle JKL, cos K= -2/3. What are the possible values for angle K?

My thought:? Book Answer: 131.8 degrees

a is right
b is 45. There is only one hundred eighty degrees in a triangle, so no angle can be 315.
c. Arc sin .25 = ?
d. Arc cos -.666 =?
I don't know what you mean by "book answer". You have to work out the arc sin/cos values.

y= -2sec4x +2. Sketch the graph include 2 full periods. Use a graphing utility to verify result

how doe's trignometry is effective in life

i need help with a coupple of problems can you help me?