6.1 day 1 Law of Sine.notebook
March 24, 2015
NOTES 6.1
COMPLETED
Solving Oblique Triangles using the LAW OF SINES
6.1 day 1 Law of Sine.notebook
March 24, 2015
Pre Calc 6.1 LAW OF SINES
solvingoblique triangles: triangles that have ________________________
To solve an oblique triangle, you need to know:
USES LAW OF SINES
1. AAS or ASA (2 angles and any side) 2. SSA (2 sides and an angle opposite one of them) USES LAW OF COSINES
3. SSS ( 3 sides)
4. SAS (2 sides and their included angle)
LAW OF SINES
IF Δ ABC HAS SIDES a,b,and c, then
sin A
a
= sin B
b
or
this is also written as
procals
the reci
o
d
o
s
l
a
can
sin B
b
= sin C
c
or
= sin C
a
c
sin A
6.1 day 1 Law of Sine.notebook
March 24, 2015
1. Solve Δ ABC given that a=8, A= 36 , B = 48
C
b=
c=
< C=
you should always show an answer box with all answers together
must
show
optional
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show
A
B
must
show
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show
6.1 day 1 Law of Sine.notebook
March 24, 2015
2. Solve Δ ABC given that a=7, b=6, A=26 18 (or 26.3 ) c=
< B=
< C=
SSA or ASS
A This is an example of an ambiguous case because 2 triangles are existing simultaneously. Depending on B
C
which piece you solve for first, second, and third, you would either get a triangle that is acute or a triangle that is obtuse. You may not know when this is occurring because you will only get one of the answers.
must show
must show
optional optional
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optional
must must show
show
must show
must show
must show
must show
optional
must show
must show
Note: Answer will be dependent on how original problem is written. If original problem uses degrees & minutes, answer must be in deg & min. If original problem only has degrees, then answer only has degrees.
6.1 day 1 Law of Sine.notebook
March 24, 2015
3. Because of prevailing winds, a tree grew so that it was leaning 6 from the vertical. At a point 30 meters from the tree, the angle of elevation to the top of the tree is 22.5 . Find the height h of the tree.
h
22.5
30 m
6.1 day 1 Law of Sine.notebook
March 24, 2015
a=
<A=
<C=
14
88
62
6.1 day 1 Law of Sine.notebook
March 24, 2015
{
HW
pg 436: 820 EVEN
21, 2934 ALL
Finding Area
of a Triangle