Question

  

Answer 1

a: ĐKXĐ: \(4x+\dfrac{\Omega}{3}\ne k\Omega\)

=>\(4x\ne-\dfrac{\Omega}{3}+k\Omega\)

=>\(x\ne-\dfrac{\Omega}{12}+\dfrac{k\Omega}{4}\)

b: ĐKXĐ: \(30^0-6x\ne90^0+k\cdot180^0\)

=>\(6x\ne-60^0-k\cdot180^0\)

=>\(x\ne-10^0-k\cdot30^0\)

c: ĐKXĐ:\(cos4x\ne0\)

=>\(4x\ne\dfrac{\Omega}{2}+k\Omega\)

=>\(x\ne\dfrac{\Omega}{8}+\dfrac{k\Omega}{4}\)

d: ĐKXĐ: \(1-sinx\ne0\)

=>\(sinx\ne1\)

=>\(x\ne\dfrac{\Omega}{2}+k2\Omega\)

e: ĐKXĐ: \(cosx+\dfrac{\Omega}{2}\ne0\)

=>\(cosx\ne-\dfrac{\Omega}{2}\)(luôn đúng)

=>\(x\in R\)