help me to answer-4[-(cos^2 45 + sin^2 45)]^1/2 > 2(-4u + u) + 3(-3u + u) this question

cos² + sin² = 1 so the left-hand side of your inequality reduces to -4i, where i is the square root of -1

The right-hand side simplifies to -12u so you have

-4i > -12u

This doesn't make a lot of sense if u is a real number, but if it is imaginary, let's say u = iw, where w is real, then:

-4i < -12iw

w < 4/12

w < 1/3

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