SOLUTION: 3. Use sum, difference, double angle, and/or half angle identities to evaluate exactly. Show all work sin(25�)*cos(35�)+cos(25�)*sin(35�)

SOLUTION: 3. Use sum, difference, double angle, and/or half angle identities to evaluate exactly. Show all work sin(25�)cos(35�)+cos(25�)sin(35�)

Question 746558: 3. Use sum, difference, double angle, and/or half angle identities to evaluate exactly. Show all work
sin(25�)*cos(35�)+cos(25�)*sin(35�)

Answer by KMST(5397) (Show Source): You can put this solution on YOUR website!
You must have been taught about trigonometric identities for sum of angles, difference, double angle, and/or half angle.
One of those identities is

If you replace and you get

where the right hand side is the expression you have to evaluate.
Since we can substitute to get
or

You should know that the exact value of is
so

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