∫[0--->π]√(sinx-sin³x)dx=∫[0--->π]√[sinx(1-sin²x)]dx=∫[0--->π]√[sinxcos²x]dx=∫[0--->π/2] cosx√(sinx)dx-∫[π/2--->π] cosx√sinx dx=∫[0--->π/2] √(sinx)d(sinx)-∫[π/2--->...