cos(4𝑥) = sin 𝑥

asked by guest
on Jan 14, 2025 at 3:53 pm



You asked:

Solve the equation cos(4x)=sin(x)\cos\left( 4 x \right) = \sin\left( x \right) for the variable xx.

MathBot Answer:

The real solutions are: x={π(1+4n)2  |  nZ}{6.2831853n+1.5707963  |  nZ}x={π(7+12n)6  |  nZ}{6.2831853n+3.6651914  |  nZ}x={π(11+12n)6  |  nZ}{6.2831853n+5.7595865  |  nZ}x={2πn+arctan(10225+5)  |  nZ}{6.2831853n+0.31415927  |  nZ}x={π+2πn+arctan(2+10255)  |  nZ}{6.2831853n+4.0840704  |  nZ}x={πarctan(10225+5)+2πn  |  nZ}{6.2831853n+2.8274334  |  nZ}x={arctan(2+10255)+2π+2πn  |  nZ}{6.2831853n+5.3407075  |  nZ}\begin{aligned}x &= \left\{\frac{\pi \left(1 + 4 n\right)}{2}\; \middle|\; n \in \mathbb{Z}\right\} \approx \left\{6.2831853 n + 1.5707963\; \middle|\; n \in \mathbb{Z}\right\}\\x &= \left\{\frac{\pi \left(7 + 12 n\right)}{6}\; \middle|\; n \in \mathbb{Z}\right\} \approx \left\{6.2831853 n + 3.6651914\; \middle|\; n \in \mathbb{Z}\right\}\\x &= \left\{\frac{\pi \left(11 + 12 n\right)}{6}\; \middle|\; n \in \mathbb{Z}\right\} \approx \left\{6.2831853 n + 5.7595865\; \middle|\; n \in \mathbb{Z}\right\}\\x &= \left\{2 \pi n + \arctan{\left(\frac{\sqrt{10} - \sqrt{2}}{2 \sqrt{5 + \sqrt{5}}} \right)}\; \middle|\; n \in \mathbb{Z}\right\} \approx \left\{6.2831853 n + 0.31415927\; \middle|\; n \in \mathbb{Z}\right\}\\x &= \left\{\pi + 2 \pi n + \arctan{\left(\frac{\sqrt{2} + \sqrt{10}}{2 \sqrt{5 - \sqrt{5}}} \right)}\; \middle|\; n \in \mathbb{Z}\right\} \approx \left\{6.2831853 n + 4.0840704\; \middle|\; n \in \mathbb{Z}\right\}\\x &= \left\{\pi - \arctan{\left(\frac{\sqrt{10} - \sqrt{2}}{2 \sqrt{5 + \sqrt{5}}} \right)} + 2 \pi n\; \middle|\; n \in \mathbb{Z}\right\} \approx \left\{6.2831853 n + 2.8274334\; \middle|\; n \in \mathbb{Z}\right\}\\x &= \left\{- \arctan{\left(\frac{\sqrt{2} + \sqrt{10}}{2 \sqrt{5 - \sqrt{5}}} \right)} + 2 \pi + 2 \pi n\; \middle|\; n \in \mathbb{Z}\right\} \approx \left\{6.2831853 n + 5.3407075\; \middle|\; n \in \mathbb{Z}\right\}\end{aligned}