MathematicsEasy45×since 2004Q5658If A=sin2x+cos4x,A = {\sin ^2}x + {\cos ^4}x,A=sin2x+cos4x, then for all real xxx:A1316≤A≤1{{13} \over {16}} \le A \le 11613≤A≤1B1≤A≤21 \le A \le 21≤A≤2C34≤A≤1316{3 \over 4} \le A \le {{13} \over {16}}43≤A≤1613D34≤A≤1{{3} \over {4}} \le A \le 143≤A≤1Check answerSkip