Question

Help With This Algebra Question

Answer 1

9514 1404 393

Answer:

(d) ±√15/4

Explanation:

Useful trig identities are ...

cos(x) = 1/sec(x)

sin(x) = ±√(1 -cos²(x))

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Using these, we see that ...

sin(θ) = ±√(1 -(1/sec²(θ))) = ±√(sec²(θ) -1)/sec(θ)

sin(θ) = ±√(4² -1)/4 = ±√15/4