3) Critically damped: [math]x(t) = (A + Bt)e^{- \gamma t}[/math] This is the optimally damped case, where the damping coefficient is just large enough to completely quell the oscillations, so the oscillator returns to zero in the least amount of time possible. 4) Overdamped: [math]x(t) = Ae^{- \gamma_{1}t} + Be^{- \gamma_{2}t}[/math]
DEAR READER: A woman is considered to be in menopause once it has been one year since her last period. Once menopause begins, vaginal bleeding is not normal. Post-menopausal bleeding (PMB) can happen for many reasons. It may result from infection or injury. Non-cancerous growths such as polyps and fibroids can cause PMB. So can bleeding disorders or use of blood thinners.
More likely, you'll experience some irregularity in your periods. Skipping periods during perimenopause is common and expected. Often, menstrual periods will occur every two to four months during perimenopause, especially one to two years before menopause. Despite irregular periods, pregnancy is possible. If you've skipped a period but aren't sure you've started the menopausal transition, you may want to determine whether you're pregnant.