# trig

if 8 tan Q=15 then sinA-cosA=?

1. 👍 0
2. 👎 0
3. 👁 182
1. or tan Q = 15/8

make a diagram, and
sin Q = 15/17 and cosQ = 8/17

you now have sinA - cosA
I hope you meant
sinQ - cosQ
= 15/17 - 8/17 = 7/17

sinQ = -15/17 and cosQ = -8/17
sinQ - cosQ = -15/17 + 8/17 = -7/17

1. 👍 0
2. 👎 0

## Similar Questions

1. ### Trigonometry

If sinA + sinB = a and cosA + cosB = b, find the value of tanA-B/2

2. ### maths

Prove SinA/1-CosA = CosecA + CotA

3. ### math

if tan=15/8 and cos negative then what is the value of [sin(-a)-cosa]/[tan(-a)+sec(-a)]

4. ### Math

if sinA+sinB=x and cosA-cosB=y then find tan[(A-B)/2]

1. ### Math

prove that sinA/(1+cosA) + (1+cosA)/(sinA) = 2cosecA

2. ### maths

sinA+cosA=p and secA+CosecA=q then show that q[p^2-1]=2p

3. ### maths

if sinA+cosA=1/5, then a value of tanA/2 satisfies which of the equation? a. 2x^2-x-1 b.x^2-2x-3=0 c.2x^2-5x-3=0 d. 2x^3-7x^2+2x+3=0

4. ### maths

If cosA + sinA= root2 cosA Show that cosA - sinA= root2 sinA

1. ### trigonometry

Prove : 1 + Sin2A/ Cos2A = CosA + SinA / CosA- SinA

2. ### maths (trigonometry)

please solve these if possible Q1. If sinx +siny=3(cosy-cosx) then the value of sin3x/sin3y. Q2. If sina ,cosa,and tan a are in g.p.then cos cubea+cos square a is equal to

3. ### further mathematics

Let P=(cosA sinA) (sinA cosA) Q=(cosB sinA) (sinB cosA) show that PQ=(cosA(A-B) sin(A B)) (sinA(A B) cos(A-B))

4. ### Maths

Given that sinA=2/5 and that A is obtuse,find the value of cosA. 👍 0 👎 0 👁 25 asked by Raj yesterday at 4:18am sinA = 2/5, so cosA = √21/5 But A is in QII, so cosA = -√21/5 👍 0 👎 0 posted by oobleck yesterday at