2010010703 Level: AIdentify the equation which arises from the following equation using an optimal substitution. 2sin2x−5cosx+1=02t2+5t−3=02t2−5t+1=02t2+5t−4=02t2−5t+2=0
2010010702 Level: AThe solution set of the equation cotgx=3 for x∈(−π;π) is:{−5π6;π6}{−π6;π6}{−π3;π3}{−2π3;π3}
2010010701 Level: AThe solution set of the equation cosx=−0.5 for x∈[0;2π] is:{2π3;4π3}{2π3;5π3}{4π3;5π3}{4π3;7π3}
2010009805 Level: CThe solution set of the inequality |cosx|≤12 for x∈R is:⋃k∈Z[π3+kπ;2π3+kπ]⋃k∈Z[−π3+kπ;π3+kπ]⋃k∈Z[π3+kπ;∞)⋃k∈Z[π3+kπ;4π3+kπ]
2010009804 Level: CThe solution set of the equation tgx−cotgx=0 for x∈R is:⋃k∈Z{π4+kπ;3π4+kπ}⋃k∈Z{kπ;π4+kπ}⋃k∈Z{π4+kπ}⋃k∈Z{3π4+kπ}
2010009803 Level: AWhich of the following equations has exactly two solutions in the interval [−π2;π2]?3cosx−2=03sinx−2=02cosx−3=03cosx+2=0
2010009802 Level: AHow many solutions does the equation cotg2x=3 have for −π≤x≤π?4 solutions2 solutions8 solutions6 solutions
2010009801 Level: AHow many solutions does the equation sin2x=0.75 have for 0≤x≤2π?4 solutions1 solution2 solutions3 solutions
2000006604 Level: BAn inequality is solved graphically as shown in the picture. The solution is marked in red. Choose the corresponding inequality.cotgx≥−33 x∈(−π;π)∖{0}cotgx≥12 x∈(−π;π)∖{0}cotgx≥32 x∈(−π;π)∖{0}cotgx≤33 x∈(−π;π)∖{0}
2000006603 Level: BAn inequality is solved graphically as shown in the picture. The solution is marked in red. Choose the corresponding inequality.cotgx≤1 x∈(−π;π)∖{0}cotgx≥1 x∈(−π;π)∖{0}tgx≤1 x∈(−π;π)∖{0}tgx≥1 x∈(−π;π)∖{0}