Cos(A-B) = cosAcosB + sinAsinB
<span>
cos(</span>π/2 - θ) = cos(π/2)cosθ + sin(π/2)sinθ
π/2 = 90°
cos(π/2) = cos90° = 0. sin(π/2) = sin90° = 1
cos(π/2 - θ) = cos(π/2)cosθ + sin(π/2)sin<span>θ
</span>
= 0*cosθ + 1*sin<span>θ = </span>sin<span>θ
Therefore </span>cos(π/2 - θ) = sin<span>θ
QED </span>
What do you need help with?
5/16 as a decimals. Divide 5 by 16 = 0.3125 times 100 = 31.25%
B
Step-by-step explanation:
Answer:
Four unique planes
Step-by-step explanation:
Given that the points are non co-planar, triangular planes can be formed by the joining of three points
The points will therefore appear to be at the corners of a triangular pyramid or tetrahedron such that together the four points will form a three dimensional figure bounded by triangular planes
The number of triangular planes that can therefore be formed is given by the combination of four objects taking three at a time as follows;
₄C₃ = 4!/(3!×(4-3)! = 4
Which gives four possible unique planes.
