Answer:
Hope this helps ^^
Explanation:
Part A: To determine the values where the pogo stick's spring will be equal to its non-compressed length, we set the function equal to zero:
f(θ) = 2cos(θ) + √3
To find the values of θ that satisfy this equation, we solve:
2cos(θ) + √3 = 0
Subtracting √3 from both sides:
2cos(θ) = -√3
Dividing by 2:
cos(θ) = -√3/2
Using the unit circle, we can find the angles where cosine is equal to -√3/2. These angles are π/6 and 11π/6.
Therefore, the values where the pogo stick's spring will be equal to its non-compressed length are θ = π/6 and 11π/6.
Part B: If the angle θ is doubled, that is, θ becomes 2θ, we substitute 2θ into the original function:
f(2θ) = 2cos(2θ) + √3
Using the double angle formula for cosine:
f(2θ) = 2(2cos²(θ) - 1) + √3
Expanding and simplifying:
f(2θ) = 4cos²(θ) - 2 + √3
Comparing this to the original function f(θ), we see that the new function has the same form but with different coefficients. The solutions for f(2θ) in the interval [0, 2π) will be the same as the solutions for f(θ), but they will occur at double the angles. In other words, if θ is a solution for f(θ), then 2θ will be a solution for f(2θ).
Part C: To find the times when the lengths of the springs from the original pogo stick and the toddler's pogo stick are equal, we set the two functions equal to each other:
f(θ) = g(θ)
2cos(θ) + √3 = 1 - sin²(θ) + √3
Rearranging the equation:
sin²(θ) + 2cos(θ) = 0
Using the Pythagorean identity sin²(θ) = 1 - cos²(θ), we substitute:
1 - cos²(θ) + 2cos(θ) = 0
Rearranging and simplifying:
cos²(θ) - 2cos(θ) + 1 = 0
Factoring:
(cos(θ) - 1)² = 0
Taking the square root:
cos(θ) - 1 = 0
cos(θ) = 1
This occurs when θ is a multiple of 2π.
Therefore, the lengths of the springs from the original pogo stick and the toddler's pogo stick are equal at θ = 2πn, where n is an integer.