I think it is -3/4 im pretty sure
Answer: i dont know if this will be correct but, the 2 goes on the bottom count 5 up so you will get the first one done, bottom 3 and count up 8, bottom 4 and count up to 13, its the same for all of them.
Step-by-step explanation:
If y = cos(kt), then its first two derivatives are
y' = -k sin(kt)
y'' = -k² cos(kt)
Substituting y and y'' into 49y'' = -16y gives
-49k² cos(kt) = -15 cos(kt)
⇒ 49k² = 15
⇒ k² = 15/49
⇒ k = ±√15/7
Note that both values of k give the same solution y = cos(√15/7 t) since cosine is even.
Answer: -3/8
Step-by-step explanation:

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