What Are the Bounds of g(t) and Solutions for Complex Equations in Trigonometry?

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For the function g(t) = 2sin(t) + cos(2t) over the interval 0 ≤ t ≤ 4π, it can be shown that -3 < g(t) < 3/2 for all t by analyzing the maximum and minimum values of the sine and cosine functions. The maximum value of g(t) is 3, and the minimum value is 1, confirming the bounds. For the equation iy/(1+ix) - (3y + 5i)/(3x + y) = 0, rearranging leads to a quadratic in y, which can be solved using the quadratic formula. Additionally, for Z = (1 + iw)/(1 + iw - w^2), simplification techniques can be applied to find |Z| and arg Z as functions of w. Understanding these concepts in calculus and trigonometry is essential for solving these complex equations.
Danielll
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Hi I've been working on my assignment for ages and am down to the last two questions (finally) which I've been working on for ages and can't work out.

1. For g(t) = 2sint+cos2t over 0 <(equal to or greater than) x < (equal to or greater than) 4pi
show that -3 < g(t) < 3/2 (< greater than or equal to) for all t.

2.a) For x and y real, solve the equation iy/(1+ix) - (3y + 5i)/(3x + y) = 0
b) Z = (1 + iw)/(1 + iw - w^2). Assume w > (greater than or equal to). Find and then sketh |Z| and arg Z as functions of w.

I really need help with these asap. Thanks in advance.
 
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Do you know calculus?It might help for the first problem...

As for 2a),by equating to 0 the # in the LHS,u'll get a system for "x" and "y".

Daniel.
 


Hi there,

I understand your frustration and the urgency in needing help with your assignment. I am happy to assist you with these questions.

1. To show that -3 < g(t) < 3/2 for all t, we can use the fact that the maximum value of sin t and cos 2t is 1. Therefore, the maximum value of g(t) is 2+1 = 3. Similarly, the minimum value of sin t and cos 2t is -1, so the minimum value of g(t) is 2-1 = 1. This means that -3 < g(t) < 3 for all t. To show that g(t) is also less than or equal to 3/2, we can use the fact that the maximum value of sin t and the minimum value of cos 2t is 1/2. This means that the maximum value of g(t) is 2+1/2 = 5/2, which is less than 3. Therefore, we can conclude that -3 < g(t) < 3/2 for all t.

2.a) To solve the equation iy/(1+ix) - (3y + 5i)/(3x + y) = 0, we can rearrange the equation to get: iy(3x+y) - (3y+5i)(1+ix) = 0. Expanding the brackets, we get: 3ixy + iy^2 - 3y - 5i - 3xy - 5ix = 0. Simplifying, we get: (3x-1)y + (x+1)y^2 - 5i = 0. This is a quadratic equation in terms of y, so we can use the quadratic formula to solve for y. Plugging in the values, we get: y = (-3x+1 +/- sqrt((3x-1)^2 + 4(x+1)5i))/(2(x+1)). This gives us two solutions for y, which we can substitute back into the original equation to solve for x.

b) To find |Z| and arg Z as functions of w, we first need to simplify Z. We can use the fact that (a+b)(a-b) = a^2 - b^2 to simplify the denominator. This gives us: Z = (1 +
 
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