Question Practice

Qn #1251
If cosθ = 4/5 and cosϕ = 12/13, θ and ϕ both in the fourth quadrant, the value of cos( θ + ϕ )is
    ❓ Question: If cosθ = 4/5 and cosϕ = 12/13, θ and ϕ both in th... | TANCET Group Studies | Tancet Group Studies