<u>ANSWER</u>
True
<u>EXPLANATION</u>
The given trigonometric equation is

Recall the double angle identity:

We apply this identity to obtain:

We maintain the LHS and simplify the RHS to see whether they are equal.
Expand the parenthesis


Recall that:


We apply these identities to get:




Also



Therefore the correct answer is True
Remark
This may be a little confusing, but because they are travelling in opposite directions, the distances add when you want to get how far apart they are.
d1 + d2 = 1541
Equation
Let the time this happens = t
d1 = 323*t
d2 = 347*t
323*t + 347*t = 1541 Combine like terms on the left.
670t = 1541 Divide by 670
t = 1541/670
t = 2.3 hours pass before the distance of 1541 miles are between the two planes. You might need the answer to be 2 hours 18 minutes.
Answer: D
Step-by-step explanation:
A P E X
Since AED forms a straight line, all involved angles sum to 180°. Therefore AEB + BED = 180. Also, since EC bisects BED, BEC = CED, and BED = 2× CED. Now to substitute the first equation:
AEB + BED = 180
AEB + 2×CED = 180
11x-12 + 2(4x+1) = 180
11x-12+8x+2 = 180
19x-10 = 180
19x-10+10 = 180+10
19x = 190
x = 10
So what is m<AEC?? It is the sum of AEB + BEC, and since BEC = CED we can say that:
AEC = AEB + CED
AEC = 11x-12 + 4x+1 = 15x-11 = 15(10)-11 = 150-11
m<AEC = 139°
The formula for the circumference of a circle is 2πr. r stands for the radius ehich is 1/2 of the diameter (the length from one edge of the circle to another on the inside of the circle). If you are estimating then you will want to change π to three and put that in for pie in the original equation.