All Obtained Different Results? Who's Right?

Students Michaelle, Maeve, Barbara and Antony, are asked to solve the equation 2sinx+cosx1=02\sin x +\cos x -1=0. Who solved it correctly?

  • Michaelle found as the solution set S={2kπ,arccos(35)+2kπ}\\\displaystyle S=\left \{ 2k\pi ,\,\arccos\left ( -\frac{3}{5} \right )+2k\pi \right \}
  • Maeve found S={2kπ,πarcsin45+2kπ}\\\displaystyle S=\left \{ 2k\pi ,\pi-\arcsin \frac{4}{5} +2k\pi \right \}
  • Barbara found S={2kπ,2arctan2+2kπ}\\\displaystyle S=\left \{ 2k\pi ,2\arctan2 +2k\pi \right \}
  • Antony found S={2kπ,π2arcsin55+2kπ}\\\displaystyle S=\left \{ 2k\pi ,\pi - 2\arcsin\frac{\sqrt{5}}{5} +2k\pi \right \}

Problem Loading...

Note Loading...

Set Loading...