Solve 7text{years}quadtext{(b)}8text{years}quadtext{(c)}9

$$7 \text { years } \quad \text { (b) } 8 \text { years } \quad \text { (c) } 9$$

Evaluate

$$504bc\left(earsy\right)^{2}$$

Solution Steps

Multiply y and y to get y^{2}.

$$7y^{2}earsb\times 8earsc\times 9$$

Multiply e and e to get e^{2}.

$$7y^{2}e^{2}arsb\times 8arsc\times 9$$

Multiply a and a to get a^{2}.

$$7y^{2}e^{2}a^{2}rsb\times 8rsc\times 9$$

Multiply r and r to get r^{2}.

$$7y^{2}e^{2}a^{2}r^{2}sb\times 8sc\times 9$$

Multiply s and s to get s^{2}.

$$7y^{2}e^{2}a^{2}r^{2}s^{2}b\times 8c\times 9$$

Multiply 7 and 8 to get 56.

$$56y^{2}e^{2}a^{2}r^{2}s^{2}bc\times 9$$

Multiply 56 and 9 to get 504.

$$504y^{2}e^{2}a^{2}r^{2}s^{2}bc$$

Differentiate w.r.t. b

$$504c\left(earsy\right)^{2}$$