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given f of x equals 5 times x minus 6 for x less than 4, equals x squared minus 2 for x between 4 and 6 inclusive, and equals 4 times x plus 10 for x greater than 6 find f ′(x) and give its domain.

5 for x less than 4, equals 2x for x greater than or equal to 4 and less than 6, and equals 4 for x greater than 6 domain: all real numbers, x ≠ 6.

5 for x less than 4, equals 2x for x between 4 and 6, and equals 4 for x greater than 6 domain: all real numbers, x ≠ 4, 6.

5 for x less than 4, equals 2x for x greater than or equal to 4 and less than 6, and equals 2 for x greater than 6 domain: all real numbers, x ≠ 4.

5 for x less than or equal to 4, equals 2x for x between 4 and 6 including 6, and equals 4 for x greater than 6 domain: all real numbers.