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>
The reason fractions need a common denominator before adding or subtracting is so that the numbers of pieces you are adding/subtracting are all the same size. Note that the numerator of a fraction just tells you how many pieces you have of that size.
Answer:
6°F
Step-by-step explanation:
Given that:
Temperature at 11pm = 48°F
Temperature at 7am = 6° cooler
Temperature at 11am = 48°F
Number of degrees temperature changed from 7am to 11 am
Exact temperature at 7am = (temperature at 11 pm - 6°)
= 48°F - 6°F
= 42°F
Temperature change from 7am to 11am
Temperature at 11 am - temperature at 7am
48°F - 42°F
= 6°F
Answer:
76.90%
Step-by-step explanation:
100/1299*999= 76.9053117783 - 100 = -23.0946882217
Answer:
2/3
Step-by-step explanation:
There are 6 marbles in the jar
4 are not purple
P(not purple) = marbles that are not purple/ total marbles
= 4/6 = 2/3