In the composition of functions, the output of g(x) is used for the input of f(x). The composition of function is f(g(x)). This mean can be said as f of g of x. In the desmos activity we have f(x)=3x+2 and g(x)=x^2. In this example I will change the input to 5.
If we plug in 5 into g(x), we get g(5)=5^2=25, this would be output and we would plug that in for the input of f(x)=3x+2.
The next step is to plug in the output which is 25 into 3(25)+2=77. The final composition would be f(g(5))=f(25)=77.
Are there other methods in solving functions? Do you find this interesting?