ত্রিকোনমিতিক ফাংশনের অন্তরজ
xxx এর সাপেক্ষে অন্তরক সহগ নিচের কোনটি? tanx−cotxtanx+cotx \frac{\tan x-\cot x}{\tan x+\cot x} tanx+cotxtanx−cotx
5sin8x5 \sin 8 x5sin8x
2sin2x2 \sin 2 x2sin2x
2cos8x2 \cos 8x2cos8x
2cos2x2 \cos 2 x2cos2x
Solve:
tanx−cotxtanx+cotx=sinxcosx−cosxsinxsinxcosx+cosxsinx=sin2x−cos2xsin2x+cos2x=−cos2x1=−cos2x∴ddx(tanx−cotxtanx+cotx)=sin2x⋅2=2sin2x \begin{aligned} & \frac{\tan x-\cot x}{\tan x+\cot x}=\frac{\frac{\sin x}{\cos x}-\frac{\cos x}{\sin x}}{\frac{\sin x}{\cos x}+\frac{\cos x}{\sin x}} \\ & =\frac{\sin ^{2} x-\cos ^{2} x}{\sin ^{2} x+\cos ^{2} x}=\frac{-\cos 2 x}{1}=-\cos 2 x \\ \therefore \quad & \frac{d}{d x}\left(\frac{\tan x-\cot x}{\tan x+\cot x}\right)=\sin 2 x \cdot 2=2 \sin 2 x \end{aligned} ∴tanx+cotxtanx−cotx=cosxsinx+sinxcosxcosxsinx−sinxcosx=sin2x+cos2xsin2x−cos2x=1−cos2x=−cos2xdxd(tanx+cotxtanx−cotx)=sin2x⋅2=2sin2x
If the functions f(x)=sin(x+a) \displaystyle f\left ( x \right )=\sin \left ( x+a \right ) f(x)=sin(x+a) and g(x)=bsinx+ccosx \displaystyle g\left ( x \right )=b\sin x+c\cos x g(x)=bsinx+ccosx satisfy f(0)=g(0) \displaystyle f\left ( 0 \right )=g\left ( 0 \right ) f(0)=g(0) and f′(0)=g′(0) \displaystyle {f}'\left ( 0 \right )={g}'\left ( 0 \right ) f′(0)=g′(0) then
dydx\displaystyle\frac{dy}{dx}dxdy at t=π4\displaystyle t=\frac{\pi}{4}t=4π for x=a[cost+12logtan2t2]\displaystyle x=a\left[\cos{t}+\frac{1}{2}\log{\tan^2{\frac{t}{2}}}\right]x=a[cost+21logtan22t] and y=asinty=a\sin{t}y=asint is
y=ln(cosx) y=\ln (\cos x) y=ln(cosx) হলে, dydx \frac{d y}{d x} dxdy এর মান কত?
y=sin(1x) y = \sin{\left ( \frac{1}{x} \right )} y=sin(x1) হলে dydx \frac{dy}{dx} dxdy এর মান-
নিচের কোনটি সঠিক?