-0,4a(2a^2+3)(5-3a^2)
- 0.4A * ( 10A^2 - 6A^4 + 15 - 9A^2) = - 0.4A*(-6A^4 + A^2 + 15) = 2.4A^5 - 0.4A^3 - 6A
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