Sin(α + β) = sinα · cosβ + cosα · sinβ
sin(π/3 + α) - √3/2cosαα α = 0,
sinπ/3 · cosα + cosπ/3 · sinα - <span>√3/2cosαα α = 0,
</span>√3/2cosαα α + cosπ/3 · sinα - <span>√3/2cosαα α = 0,
</span><span>cosπ/3 · sinα = 0,
</span>1/2 · <span>sinα = 0,
</span><span>sinα = 0,
</span>α = πn, n ∈ Z
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f(-3)=5(-3)^2=5*9=45
f(a^3)=5(a^3)^2=5a^6
f(a-3)=5(a-3)^2=5(a^2-6a+9)=5a^2-30a+45
f(3x)=5(3x)^2=5*9x^2=45x^2