Question

The order of the differential equation of family of curves $y=\tan \left(\frac{\pi}{4}+a x\right) \tan \left(\frac{\pi}{4}-a x\right)+c e^{b x+d}$ is (where a, b, c, d are parameters)

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

Answer: (B)

$y=\frac{1+\tan a x}{1-\tan a x} \cdot \frac{1-\tan a x}{1+\tan a x}+\left(\operatorname{ce}^d\right) e^{b x}=1+k e^{b x}$
two arbitary constant
$\therefore$ order 2