sabaahmed900 sabaahmed900
  • 02-10-2020
  • Mathematics
contestada


a
2
=
b
2
+
c
2
−
2
b
c
cos
A
Evaluate
cos
A
given that
a
=
8
,
b
=
6
and
c
=
7
.

Respuesta :

Erlea
Erlea Erlea
  • 02-10-2020

Answer:

a^2=b^2+c^2- 2bc cosA

64= 36+ 49 - 2(6)(7)cos A

64- 85 = 84cos A

84 cosA= -21

cos A= -21/84

cosA= -0.25

Answer Link

Otras preguntas

How does the saguaro cactus take advantage of rare, brief rainfall?
1/7(x+21)=-6 answer ?
A box is lowered using a rope. If the acceleration of the box, is 2.5 m/s2 (downward) and the tension in the rope is 31 N, what is the mass of the box (in kg)?
A box is lowered using a rope. If the acceleration of the box, is 2.5 m/s2 (downward) and the tension in the rope is 31 N, what is the mass of the box (in kg)?
2h/3-1/4=1/3 solve and show your steps
what is the value for the expression -5+ 5
What is the value of 1-18+25 if you subtract then add? If you add then subtract?Why is order of operations necessary?
If 604-72=___,then 532+___=604.Explain the process of checking your work.
What's 45 out of 58 in percentage?
List the perfect squares between 100 and 500 that are even numbers