Problem description below known expressions:

Q1=1 - p/s;
Q2=1 - p2/p1 (1 - phi) * s +/s - p2/s;
PI=(p1 + p2 * * q1 q2;

For maximum profit PI and the corresponding values of q1 and q2.

Note: parameters phi ∈ [0, 1], p1, p2, q1 and q2, s were greater than 0

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