Evaluate 1+sinx1-sinx
Consider 1+sinx1-sinx
On multiply and divide by 1+sinx i.e,
1+sinx1-sinx×1+sinx1+sinx1+sinx212-sin2x1+sinx2cos2x1+sinxcosx21cosx+sinxcosx2secx+tanx2
Hence, 1+sinx1-sinx=secx+tanx2
Evaluate the expression when x=-45andy=13
2x+6y
loge(n+1)−loge(n−1)=4a[(1n)+(13n3)+(15n5)+...∞] Find 8a.