2cos(x) - 4sin(x) = 3
use identity [cos(x)]^2 +[ sin(x)]^2 = 1 => cos(x) = √[1 - (sin(x))^2]
2√[1 - (sin(x))^2] - 4 sin(x) = 3
2√[1 - (sin(x))^2] = 3 + 4 sin(x)
square both sides
4[1 - (sin(x))^2] = 9 + 24 sin(x) + 16 (sin(x))^2
expand, reagrup and add like terms
4 - 4[sin(x)]^2 = 9 + 24sin(x) + 16sin^2(x)
20[sin(x)]^2 + 24sin(x) +5 = 0
use quadratic formula and you get sin(x) = -0.93166 and sin(x) = -0.26834
Now use the inverse functions to find x:
arcsin(-0.93166) = 76.33 degrees
arcsin(-0.26834) = 17.30 degrees
Sine rule
a/Sin(A) = b/Sin(B) = c/Sin(C)
b
C / |
a / _| A
B c
We know that a = 70 degrees and A = 25 foot
So 70/Sin(25) = Something
We also know we want C, and that c = 90 degrees
So 70/Sin(25) = 90/Sin(C)
Then you have to rearrange the equations. Start with Multiply all by Sin(C)
So [Sin(C)][70/Sin(25)] = 90
Then divide everything by 70/Sin(25)
So Sin(C) = 90/[70/Sin(25)]
Now you want to isolate C, so Sin-1 everthing
So C = Sin-1{90/[70/Sin(25)]}
So C = 32.91309534
To the nearest tenth, 32.9ft
Hope that helps :)
ANSWER: 219.375
subtract the second day from the first day.
547.250-327.875=219.375
1mm = .11m
You can get this by simplifying the numbers you already have
Answer:
The expression means that X+20
