Theory |
by Example Series Trigonometric Identity |
Using Law of Sines to find B: .7377
=> B = sin -1 = 47.540 So C = 180 - (40.2 + 47.54) = 92.260
Using Law of Sines to find c:
A=40.20
B=47.540 C= 92.260 A=7ft, b=8ft and c=10.84 ft |
Question 2. Find all solutions to in interval
=> 300 and -300 for cos (-)
So |
Question 3 - Given that the in the 4th quadrant: Find:
(a) (b) (c)
In Q-IV:
So
(a)
(b)
(c)
Question 4. Find all solutions to 3 in the interval
19.470 tan is also (+) in Q-III so 180+19.47 is also a solution: 199.470
So solutions
Question 5 - A kite flyer wondered how high her kite
was flying.
She used a protractor to measure an angle of 380
from level ground
to the kite string. If she used a full 100 yard spool
of string, how high, in feet,
was the kite ? (disregard the string sag and height
of the reel above the ground).
Given A = 380, hyp = 100 yds or 100 x 3 = 300 feet: Find opposite side:
Question 6. Solve the following triangle: B = 135 deg
4 min, a= 3 cm
and c = 5 cm. B = 135 + 4/60 deg = 135.06667
Law of cosines: Find side b: =55.2379
Law of Sines to find A: 0.2851
A => 16.560 [sin-1 (0.2851)]
So C = 180 - (135.07 + 16.56) = 28.230
A = 16.560
C = 28.230 b = 7.4322 cm |
Question 7. Find all solutions to in interval
Since
Use identity with sin(x):
Substitute:
: let
So:
Replace
So (a) sin also (+) in Q-II therefore
(b) or
sin also = 0 at 1800
Question 8. Find all solutions to in interval
Since
Then
So:
Or: