 Using radian measure for angle, and putting formula_4, one gets

The assonance of "formula_6" and "formula_7" makes this expression especially pleasing as a mnemonic.To express the previous formula with the constant formula_8 one can useformula_9 

Equivalent forms of Bhaskara I's formula have been given by almost all subsequent astronomers and mathematicians of India.For example, Brahmagupta's (598 – 668 CE)
"Brhma-Sphuta-Siddhanta" (verses 23 – 24, Chapter XIV) gives the formula in the following form