a) A system is "linear" whenever its output y(t)=A x(t) + B for some constants A and B. (TRUE or FALSE?) b) If you input a signal x₁(t) into a linear system and obtains y₁(t); then the output of the system when you later input a signal -4x1(t) will be -4y₁(t). (TRUE or FALSE?) c) A system is called "time invariant" if its output y(t) does not change over time; i.e. y(t) equals a constant. (TRUE or FALSE?)

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Linear System:-

• A linear system is a mathematical representation of a system in systems theory that relies on the application of a linear operator. 
• Compared to nonlinear systems, linear systems often have significantly simpler traits and properties.

Non-Linear System:-

• A larger class of systems that do not adhere to the superposition principle are covered by nonlinear control theory. 
• Since all genuine control systems are nonlinear, it applies to more real-world systems. 
• In many cases, nonlinear differential equations regulate these systems.