Question

Can someone help me out with this question plz

Answer 1

Answer:

$\left(s\cdot t\right)\left(x\right)=2x^2+12x+16$

$\left(s-t\right)\left(x\right)=-x$

$\left(s+t\right)\left(4\right)=20$

Step-by-step explanation:

Given functions are:

$s\left(x\right)=x+4$

$t\left(x\right)=2x+4$

Then $\left(s\cdot t\right)\left(x\right)=s\left(x\right)\cdot t\left(x\right)$

or $\left(s\cdot t\right)\left(x\right)=\left(x+4\right)\left(2x+4\right)$

or $\left(s\cdot t\right)\left(x\right)=2x^2+4x+8x+16$

or $\left(s\cdot t\right)\left(x\right)=2x^2+12x+16$

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Similarly

$\left(s-t\right)\left(x\right)=s\left(x\right)-t\left(x\right)$

or $\left(s-t\right)\left(x\right)=\left(x+4\right)-\left(2x+4\right)=x+4-2x-4$

or $\left(s-t\right)\left(x\right)=-x$

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Similarly

$\left(s+t\right)\left(4\right)=s\left(4\right)+t\left(4\right)=\left(4+4\right)+\left(2\left(4\right)+4\right)=\left(8\right)+\left(12\right)=20$

$\left(s+t\right)\left(4\right)=20$