A few days ago

Any math genius help me with these questions please thanks!!!?

Math problems need big help by tonight Pre-Calc.?

I used this symbol as pi π

Suppose that sec a= 5/4 and tan b= -1, where 0

Top 1 Answers
A few days ago
jennie s

Favorite Answer

you need to use the formula of

cos(a+b)= cos a cos b – sin a sin b

if you follow the formula,i am sure you can get the answers.

sec a = 5/4

1/cos a = 5/4

cos a = 4/5. by using theorem pythagoras,you will find tha sin a = 3/5

then,tan b = -1

sin b/ cos b = -1

so,sin b = -cos b

then,you substitute into the formula.

you will get the answers…try it..

sorry about i din write all working here coz it is very hard to write…