That's not true at all. The ti30 and relatives are arguably one of the most well known scientific calculators in the world, and it uses 2nd. http://i.ebayimg.c

That's not true at all. The ti30 and relatives are arguably one of the most well known scientific calculators in the world, and it uses 2nd. http://i.ebayimg.com/00/$T2eC16FHJH4FHejHUSZ3BSB3Dzh6%20g~~_32.JPG http://i.ebayimg.com/00/$T2eC16FHJH4FHejHUSZ3BSB3Dzh6%20g~~_... The hp35 and relatives use an upper and lower "shift" button to access the inverse trig functions. http://i.ebayimg.com/images/i/251900074306-0-1/s-l1000.jpg http://i.ebayimg.com/images/i/251900074306-0-1/s-l1000.jpg