Решение 

`>=`(`*`(`*`(`+`(`*`(5.7, `*`(`^`(10, -8)))), `/`(1, 16)), `*`(`^`(10, 20), `*`(`^`(T, 4)))), `+`(`*`(9.12, `*`(`^`(10, 25)))))[[`<=`(T, -4000.)], [`<=`(4000., T)]]