Pre Cal.

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So I posted these...but no one answered them. Are they right?

Solve 4sin^2 x + 4sqrt(2) cos x-6 = 0 for all real values of x.

My answer: (pi/4)+2(pi)k, (7pi/4) + 2(pi)k

Solve 2cos^2 x-5cosx+2=0 for principal values of x.

My answer: 60 and 300 degrees

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