Can someone help with number 4. I will reward brainliest.
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Answer:
theta = pi/6 and
theta = 5pi/6
Step-by-step explanation:
see image. Factor the expression. Solve for sin theta. Then use a calculator or unit circle to solve for theta. See image.
Let's simplify the problem down a little:
⇒ set 'sin(θ)' as x
⇒ the new equation looks like: [tex]2x^2+5x-3=0[/tex]
Now let's solve this equation as a quadratic:
[tex]2x^2+5x-3=0\\(2x-1)(x+3)=0\\\\2x-1=0\\x = \frac{1}{2} \\\\x+3 = 0\\x=-3[/tex]
Now set the x value of '1/2', to sin(θ)
sin(θ) = 1/2
θ = π/6, which is between the range given
Answer: π/6
Hope that helps!