Answer:
Shift 1 units towards left and then stretch vertically 3 times.
Explanation:
We are given that a parent function
![y=x^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/119iel6l5tkcn7b4lhapzm9adpkt0zn3jo.png)
After transformation, we get a graph
![y=3(x+1)^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/5dmqwjo5zpct0rna0jogrefsoyqqbsqa3c.png)
We have to find that how the parent function transformed to produce the graph of
![y=3(x+1)^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/5dmqwjo5zpct0rna0jogrefsoyqqbsqa3c.png)
The parent graph is shifted 1 unit towards left by the rule of transformation
By applying this rule then, we get
![y(x)=(x+1)^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/4dq81bumq3ral5vcwyf1i5pkm1rohzb9nw.png)
Now, the parent function stretched vertically 3 times the previous graph by the rule
Apply this rule then, we get
![y(x)=3(x+1)^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/knbahqtt4fnubpqrseedojuuf254n06bxh.png)