Answer: 10 - 2√21
Step-by-step explanation: I simplified your question by using an online calculator. :)
Answer:
cos x (2 sin x − 1)
Step-by-step explanation:
sin(2x) − cos x
Use double angle formula.
2 sin x cos x − cos x
Factor.
cos x (2 sin x − 1)
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6+4:2*10
6+2*10
<h2>26</h2>
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Work in amount of pure acid let x = gallons of pure acid required.
then we have the equation:-
x + 55(0.6) = 0.80(x + 55)
x + 33 = 0.80x + 44
0.20x = 11
x = 11/0.2 = 55 gallons answer
The answer could be 45 but I'm not entirely sure
