Question

sin2a, если cosa-sina=0,5

Answer 1

$cosa-sina=0,5\\\(cosa-sina)^2=cos^2a-2sinacdot cosa+sin^2a=1-2sinacdot cosa;\\0,5^2=1-2sinacdot cosa; ; to ; ; 2sinacdot cosa=1-0,5^2=0,75; ;\\\sin2a=2sinacdot cosa=0,75$