Question
Solve the following equations:
$2^{\sin^2\text{x}}+2\cos^{2\text{x}}=2\sqrt{2}$

Answer

$2^{\sin^2\text{x}}+2\cos^{2\text{x}}=2\sqrt{2}$
$\Rightarrow2^{\sin^2​\text{x}}+2\cos^{-1\sin^2\text{x}}=2\sqrt{2}$
$\Rightarrow2^{\sin2\text{x}}+\frac{2}{2\sin^2\text{x}}2\sqrt{2}$
$\text{Let}2^{\sin^2\text{x}}+\frac{2}{2^{\sin2\text{x}}}=\text{y}$
$\Rightarrow\text{y}+\frac{2}{\text{y}}=2\sqrt{2}$
$\Rightarrow\text{y}^2+2=2\sqrt{2\text{y}}$
$\Rightarrow\text{y}^2-2\sqrt{2\text{y}}+2=0$
$\Rightarrow\text{y}^2-2\sqrt{2\text{y}}-\sqrt{2}\text{y}-\sqrt{2\text{y}}+2=0$
$\Rightarrow\text{y}\Big(\text{y}-\sqrt{2}\Big)-\sqrt{2}\Big(\text{y}-\sqrt{2}\Big)=0$
$\Rightarrow\Big(\text{y}-\sqrt{2}\Big)^2=0$
$\Rightarrow\Big(\text{y}-\sqrt{2}\Big)=0$
$\Rightarrow​​\text{y}=\sqrt{2}$
$\Rightarrow2^{\sin^2​​\text{x}}=2\frac{1}{2}$
$\Rightarrow\sin^2​​\text{x}=\frac{1}{2}$
$\Rightarrow\sin^2\text{x}=\sin^2\frac{\pi}{4}$
$\Rightarrow\text{x}=\text{n}\pi\pm\frac{\pi}{4},\text{n}\in\text{Z}$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Similar questions

Find the conditions that the straight lines $y = m_1x + c_1, y = m_2x + c_2$ and $y = m_3x + c_3​​​​​​​$​​​​​​​may meet in a point.
A solution of 9% acid is to be diluted by adding 3% acid solution to it. The resulting mixture is to be more than 5% but less than 7% acid. If there is 460 litres of the 9% solution, how many litres of 3% solution will have to be added?
A man arranges to pay off a debt of ₹ 3600 by 40 annual instalments which form an arithmetic series. When 30 of the instalments are paid, he dies leaving one-third of the debt unpaid, find the value of the first instalment.
Show that the solution set of the following linear in equations is an unbounded set:
$\text{x}+\text{y}\geq9,3\text{x}+\text{y}\geq12,\text{x}\geq0,\text{y}\geq0.$
Find the tangent of the angle between the lines which have intercepts $3, 4 $and $1, 8$ on the axes respectively.
Prove the following by using the principle of mathematical induction for all n ∈ N:
$\frac{1}{3.5}+\frac{1}{5.7}+\frac{1}{7.9}+...+\frac{1}{(2\text{n}+1)(2\text{n}+3)}=\frac{\text{n}}{3(2\text{n}+3)}.$
Prove the following statement by principle of mathematical induction:
$1 + 5 + 9 + ...... + (4n - 3) = n(2n - 1),$ for all natural numbers $n.$
Find the equation of the circle, the end points of whose diameter are $(2, -3)$ and $(-2, 4).$ Find its centre and radius.
Prove that:
$\tan\text{x}\tan\Big(\frac{\pi}{3}-\text{x}\Big)\tan\Big(\frac{\pi}{3}+\text{x}\Big)=\tan3\text{x}$
Prove the following by the principle of mathematical induction:
$\frac{1}{3.5}+\frac{1}{5.7}+\frac{1}{7.9}+...+\frac{1}{(\text{2n+1)(2n+3)}}=\frac{\text{n}}{3(\text{2n}+1)}$