Solve secx - cotx = cscx - tanx
Solve 1+1+2/(1-tan²x )-(3-tan²x)/(1-3 tan²x )=0
Prove that:tan-11/3+tan-11/5+tan-11/7+tan-11/8=45°
Prove that:(sin75°+sin15°)/(sin75°-sin15°)=tan60°
Transform the difference of two squares into a rectangle, the ratio of two sides being 2 : 3.
Evaluate to four significant figure by logarithm,
Simplify yz(x+a)/(x-y)(x-z)+zx(y+a)/(y-z)(y-x)+xy(z+a)/(z-x)(z-y)
函数f(x)=cosx+(x+1)sinx+1在区间[0,2π]的最小值、最大值分别为【 】
已知cosx=(1-(M+1)sin2x)/(1+(M-1)sin2x),求x的值.
英:Solute the equation汉:解方程sin4θ+sinθ=0
Find all the positive angles less than 380° which satisfy the equation sinx+sin2xsin3x = 0.
Find all the positive angles less than 360° which satisfy the equation:cos2x+cosx+1=0