Please help precalc Use trigonometric identities to solve each equation within the given domain.
1. –sin^2(x) = cos(2x) from [–π,π]

2. 3 tan(x) = 2 sin(2x) from [0,2π)

3. sec(x) cos(3x) = 0 from [–π /2, π /2]

4. sec(x) cos(3x) = 0 from [–π/2, π/2]

5. "4cos^4(x) – 5cos^2(x) + 1 = 0 from [0,2π)

Suppose there is a simple index of three stocks, stock abc, stock xyz, and stock qrs. stock abc opens on day 1 with 4000 shares at $3.15 per share. stock xyz opens on day 1 with 5000 shares at $4.30 per share. stock qrs opens on day 1 with 6000 shares at $4.60 per share. the price of stock abc on day 8 begins at $3.50. the price of stock xyz on day 8 begins at $3.90. stock qrs opens on day 8 with a price of $4.50 per share. assume that each stock has the same number of shares that it opened with on day 1. what is the rate of change of this simple index over 1 week?

What is the equation of the graph below? y=sec(x)-4

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