Trigonometric EquationHard
Question
sec2 θ =
is true if and only if
is true if and only ifOptions
A.x = y ≠ 0
B.x = y, x ≠ 0
C.x = y
D.x ≠ 0, y ≠ 0
Solution
We know that, θ ≥ 1
⇒
⇒ 4xy ≥ (x + y)2
⇒ (x + y)2 - 4xy ≤ 0
⇒ (x + y)2 ≤ 0
⇒ x - y = 0
⇒ x = y
Therefore, x + y = 2x (add x both sides)
But x + y ≠ 0 since it lies in the denominator,
⇒ 2x ≠ 0
⇒ x ≠ 0
Hence, x = y, x ≠ 0 is the answer.
Therefore, (a) and (b) are the answers.
⇒

⇒ 4xy ≥ (x + y)2
⇒ (x + y)2 - 4xy ≤ 0
⇒ (x + y)2 ≤ 0
⇒ x - y = 0
⇒ x = y
Therefore, x + y = 2x (add x both sides)
But x + y ≠ 0 since it lies in the denominator,
⇒ 2x ≠ 0
⇒ x ≠ 0
Hence, x = y, x ≠ 0 is the answer.
Therefore, (a) and (b) are the answers.
Create a free account to view solution
View Solution FreeMore Trigonometric Equation Questions
If sec θ + tan θ = P then the value of sin θ is -...The number of values of x in the interval [0,5π] satisfying the equation [0,5π] is...If system of equations x + 2y + 3z = 2, 2x + 3y – (2sinθ)z = 9 and 3x + 5y + 2z = √3 sec θ + 9 haveinf...Let n be a positive integer such that sin + cos = . Then :...Let θ ∈ and t1 = (tan θ)tan θ, t2 = (tan θ)cot θ, t3 = (cot θ)tan θ and t4 = (c...