What is the equation of a parabola that opens left with a vertex of (-1,1)

Hello i need some with trigonometric substitutions. [tex]\int\limits^a_b {x} \, dx[/tex]

Which of the fallowing best completes the sequence 12,8,5, a) 1 b) 2 c)4 d)0

Acompany that manufactures and sells guitars made changes in their product range. from the start they had 20 models. then they reduced the number of models to 15. as a result, the company enjoyed a 10% increase in turnover. - how much did the stock level change? in (%)