Answer:
4 + 8 x - 435=0
Step-by-step explanation:
Let x be any natural number
Let the age of Bill= 2 x+ 1 years (Since age is odd integer)
Than, age of a Susan= 2 x + 3 years
Since ages are consecutive odd integers
According to question
(2 x+1)(2 x+ 3)= 438
4 + 8 x + 3 = 438
4 + 8 x + 3 - 438 =0
4 + 8 x - 435=0
This equation can be used to find the ages of both
Hence, the correct answer is 4 + 8 x - 435=0
Answer:
Step-by-step explanation:
It is convenient to memorize the trig functions of the "special angles" of 30°, 45°, 60°, as well as the way the signs of trig functions change in the different quadrants. Realizing that the (x, y) coordinates on the unit circle correspond to (cos(θ), sin(θ)) can make it somewhat easier.
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<h3>20.</h3>You have memorized that cos(x) = (√3)/2 is true for x = 30°. That is the reference angle for the 2nd-quadrant angle 180° -30° = 150°, and for the 3rd-quadrant angle 180° +30° = 210°.
Cos(x) is negative in the 2nd and 3rd quadrants, so the angles you're looking for are
150° and 210°
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<h3>Bonus</h3>You have memorized that sin(π/4) = √2/2, and that cos(3π/4) = -√2/2. The sum of these values is ...
√2/2 + (-√2/2) = 0
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<em>Additional comments</em>
Your calculator can help you with both of these problems.
The coordinates given on the attached unit circle chart are (cos(θ), sin(θ)).
