Solve fro x.
Thank you a lot!
4sin^4(x)-1=0?
2016-03-27 11:02 pm
回答 (2)
2016-03-28 12:10 am
Put s=sinx. Then 4s^4=1, s^4 =(1/4), s^2 =(1/2), s =(+/-)(1/rt2).
Then, on (0,2pi), x = pi/4, 3pi/4, 5pi,4, 7pi/4 are all solutions for
the eqn 4sin^4(x) = 1.
Then, on (0,2pi), x = pi/4, 3pi/4, 5pi,4, 7pi/4 are all solutions for
the eqn 4sin^4(x) = 1.
2016-03-27 11:04 pm
sin(x) = 1/sqrt2 --->x = pi/4 , 3pi/4
sin(x) = -1/sqrt2 --->x = 5pi/4 , 7pi/4
4 solutions
sin(x) = -1/sqrt2 --->x = 5pi/4 , 7pi/4
4 solutions
收錄日期: 2021-04-21 17:42:28
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