Answer:
68
Step-by-step explanation:
I think Deal B correct me if im wrong..
Answer:
[45tan(82°)+123] meters
A is correct
Step-by-step explanation:
You are standing 45 meters from the base of the Empire State Building.
You estimate that the angle of elevation to the top of the 86th floor(the observatory) is 82°.
If the total height of the building is another 123 meters above the 86th floor.
OB = 45 m , ∠O= 82°
In Δ OBA, ∠B = 90°



Top of the building, T at 123 m from A
Total height of building = BA + AT

Hence, The height of building from ground is [45tan82°+123] meters
You can do this with foil
F(which is the first term of both factors): 4*sqrt(7)
O(outside terms of both factors first and last) 4*sqrt(2)
I (Inside terms 2nd and 3rd) = - sqrt(3) sqrt(7) = - sqrt(21)
L (Last term in each of the factors) - sqrt(3)*sqrt(2) = - sqrt(6)
Combine terms: 4*sqrt(7) + 4*sqrt(2) - sqrt(21) - sqrt(6) <<<< answer.
Hello,
A)
cos 135°=- cos 45°=-√2/2
sin 135°=sin45°=√2/2
2(cos 135°+i sin 135°)=-√2 + i*√2
B)
cos 120°=-cos 30°=-√3 /2
sin 120°=sin 30°=1/2
3(cos 120° + i sin 120)=-3/2*√3 +i*3/2
C)
cos (5π/4)=-cos (π/4)=-√2 /2
sin (5π/4)= -sin(π/4)=-√2 /2
5(cos (5π/4)+i sin (5π/4))=-5/2*√2 +i *5/2*√2
D)
cos(5π/3)=cos(π/3)=√3 /2
sin (5π/3)=-sin(π/3)=-1/2
4(cos(5pi/3)+i sin (5pi/3))
=2√3- 2*i