(Prove that):
2 sin 70. cos 20 = sin 90 + sin 50​

see explanation

Step-by-step explanation:

Using the trigonometric identity

2sinxcosy = sin(x + y) + sin(x - y) , then

with x = 70 and y = 20

2sin70cos20

= sin(70 + 20) + sin(70 - 20)

= sin90 + sin50

= right side , thus proven

by definition, an arc subtended by a central angle of some given measure has the same measure. so .

a

step-by-step explanation:

rurbrbrjrnrbjr