?
If 3(cot2θ - cos2θ) = cos2θ, 0°< θ < 90°, then the value of (tan2θ + cosec2θ + sin2θ) is:
Answer & Solution
Correct Answer:
Option
B
$$\eqalign{
& 3\left( {{{\cot }^2}\theta - {{\cos }^2}\theta } \right) = {\cos ^2}\theta \cr
& 3{\cot ^2}\theta = {\cos ^2}\theta + 3{\cos ^2}\theta \cr
& 3{\cot ^2}\theta = 4{\cos ^2}\theta \cr
& \frac{3}{4} = {\sin ^2}\theta \cr
& \sin \theta = \sin {60^ \circ } \cr
& \theta = {60^ \circ } \cr
& {\tan ^2}\theta + {\text{cose}}{{\text{c}}^2}\theta + {\sin ^2}\theta \cr
& = {\tan ^2}{60^ \circ } + {\text{cose}}{{\text{c}}^2}{60^ \circ } + {\sin ^2}{60^ \circ } \cr
& = 3 + \frac{4}{3} + \frac{3}{4} \cr
& = \frac{{36 + 16 + 9}}{{12}} \cr
& = \frac{{61}}{{12}} \cr} $$
Join the Discussion
Login to post a comment or share your explanation.
Login