1lakh=______thousand
1lakh=1,00,0001Thousand=1000
Now,
1lakh1thousand=1,00,00010001lakh1thousand=1001lakh=100×1thousand
Hence, 1lakh=Hundredthousands
Evaluate tan-1x+tan-1y+tan-11-x-y-xy1+x+y-xy
Evaluate tan-1c1x-yc1y+x+tan-1c2-c11+c2c1+tan-1c3-c21+c2c3+…+tan-11cn:
If y=sec-1[cosecx]+cosec-1[secx]+sin-1[cosx]+cos-1[sinx],dydx is equal to
1+cosθ1-cosθ+1-cosθ1+cosθ=2cosecθ.
1+sinθ1-sinθ+1-sinθ1+sinθ=2secθ.