Question

State lenz's. show that lenz's law follows from priciple of

Answer 1

An induced  (emf) always gives rise to a current whose magnetic field opposes the change in orignal magentic flux.
or we can say that the current whose magnetic field is opposite to the field which produced it . 

like if flux will be increasing then the current will oppose it and will tends decrease it , 
and if flux is decreasing then the current produced will be in such a direction then magnetic field due to current  oppose the flux and will tends to increase it 

Answer 2

Answer:

$\mathtt \red{\int ( \frac { 2 + 3 \cos x } { \sin ^ { 2 } x } ) d x}$