radomes.openskiesproject.org
ngoann4 ngoann4
  • 30-03-2015
  • Mathematics
Answered

Verify as an identity: cos(90°+x) = -sinx

I'm not sure how to go about this question

Verified Answer :

crisforp
crisforp crisforp
  • 30-03-2015

cos( a + b ) = cosa×cosb - sina×sinb ; 
a = 90 and b = x ;
But, cos90 = 0 and sin90 = 1;
cos( 90 + x ) = 0 × cosx - 1 × sinx = - sinx ;

Answer Link

Related Questions

Regarding the Electoral College which of the following statements is false A If there were 600 electors 301 electoral votes would win the presidential election
Explain the contents of use policy in the following contexts workplace home educational establishment
you are told that the value of a car of the given model based on its age is less than 6000 Give a range of values that could represent the age of the car
Jeanine Baker makes floral arrangements She has 14 different cut flowers and plans to use 4 of them How many different selections of the 4 flowers are possible
Three ways to make a solute dissolve faster in a solvent
Who is believed to be the head of the Roman Catholic Church
Can someone please tell me if this is right If not whats the right answer Theres a picture too
Write the expression 5xx 9 7x 9 in complete factored form
A 200foot long support wire attaches to a cell phone tower at a height of 50 feet from the ground To the nearest tenth of a foot what is the distance along the
What did the Puritans form to establish their own New World colony Athe Mayflower Compact Bthe Virginia Company Cthe Jamestown settlement Dthe Massachusetts Bay