Solve (1,8s^2-1,4r^2)+(0,5rs-1,2r^2+2,4s^2)

$$( 1,8 s ^ { 2 } - 1,4 r ^ { 2 } ) + ( 0,5 r s - 1,2 r ^ { 2 } + 2,4 s ^ { 2 } )$$

Evaluate

$$\frac{rs}{2}+\frac{21s^{2}}{5}-\frac{13r^{2}}{5}$$

Solution Steps

Combine -1,4r^{2} and -1,2r^{2} to get -2,6r^{2}.

$$1,8s^{2}-2,6r^{2}+0,5rs+2,4s^{2}$$

Combine 1,8s^{2} and 2,4s^{2} to get 4,2s^{2}.

$$4,2s^{2}-2,6r^{2}+0,5rs$$

Differentiate w.r.t. s

$$\frac{r}{2}+\frac{42s}{5}$$