<span>To use Law of Cosines, you need to know an angle and two sides.
The simplest case is if you know two sides (a and b) and the included angle (C)
c² = a² + b² − 2ab cos(C)
cos(A) = (b² + c² − a²) / (2bc)
cos(B) = (a² + c² − b²) / (2ac)
You can also use Law of Cosines if you know 2 sides (b and c), and non-included angle (C). We use first equation above, solving for a. Since the equation is a quadratic (with respect to unknown variable a), it is simpler to use Law of Sines in this case.
You can also use Law of Cosines if you know the 3 sides (a,b,c)
cos(A) = (b² + c² − a²) / (2bc)
cos(B) = (a² + c² − b²) / (2ac)
cos(C) = (a² + b² − c²) / (2ab)</span>
1. Corresponding
2. Angle 8
Answer:
The volume of the hemisphere
V = 121.33086 cubic centimeter
Step-by-step explanation:
<u>Step(i)</u>:-
Given that the total surface area of a hemisphere = 45π cm²
<em> The total surface area of a hemisphere = 3π r²</em>
Equating
3π r² = 45π

r = 
The radius of the sphere 'r' = 3.87
<u><em>Step(ii):-</em></u>
<em>The volume of the hemisphere</em>


we know that π = 3.14

V = 121.33086 cubic centimeter
Are of circle = πr² = 22/7 *4*4 = 50.27cm²