geometry b bellwork 3) using the inverse of tangent find m n to the nearest degree. tan n = = m n =...

Geometry B Bellwork3) Using the inverse of tangentFind m N to the nearest degree.

tan N = = m N = tan-1(0.6) m N ≈ 31°

N

R X

30

18

18 30

0.6

9-2 Sine and Cosine Ratios

sin A =opposite side

hypotenuse

sin A = a

c

B c a

C b A

cos A =adjacent side

hypotenuse

cos A = b

c

B c a

C b A

EX. Write the sine and cosine ratio for A and B.

sin A =

cos A =

sin B =

cos B =

A

B

C

8 17

15

Before starting this problem change your calculator mode to degrees

EX 2. Find the value of w to the nearest tenth

cos =

5.1≈ w w32°

632° w 6

(6)cos 32°=w

1

CROSS

MULTIPLY

Before starting this problem change your calculator mode to degrees

Ex 3 . Find the value of w to the nearest tenth

sin =

7.1 ≈ w

w

52°

9

52° w 9

(9)sin52°=w

1

CROSS

MULTIPLY

Before starting this problem change your calculator mode to degrees

OYO….Find the value of w to the nearest tenth

sin =

8.6 ≈ ww

46°

12

46° w 12

(12)sin46°=w

1

CROSS

MULTIPLY

Before starting this problem change your calculator mode to degrees

EX 4. Find the value of w to the nearest tenth

cos =

w ≈ 10.7

w

62° 5

62° 5 w

cos62°(w)= 5

1

cos62° cos62°

CROSS

MULTIPLY

Before starting this problem change your calculator mode to degrees

OYO. Find the value of w to the nearest tenth

sin =

w ≈10.3

w

43°

743° 7

w

sin43°(w)= 7

1

sin43° Sin 43°

CROSS

MULTIPLY

EX. 5 Using the inverse of tangentFind m X to the nearest degree.

cos X = = m X = cos-1( ) m X ≈ 55°

N

R X

14

8

814

0.571428571

0.571428571

OYO….Using the inverse of tangentFind m X to the nearest degree.

sin X = = m X = sin-1( ) m X ≈ 43°

N

R X

1913

1319

0.684210526

0.684210526