The equation is 2 cos−1 x+sin−1 x=11π6 has [AMU 1999}
Only one solution
Two solutions
Three solutions
Given equation is (2 cos−1 x+sin−1 x=11π6 ⇒cos−1 x+(cos−1 x+sin−1x)=11π6⇒cos−1 x+π2=11π6⇒cos−1 x+4π/3 which is not possible as cos−1 x ε[0,π]
The pair of equations y = 0 and y = -7 has :