\(14,\\ a,B=\left(2x+1\right)^3=\left(2\cdot\dfrac{1}{2}+1\right)^3=2^3=8\\ b,C=\left(x+2y-2\right)^3=\left(20+2\cdot1-2\right)^3=20^3=8000\\ 15,\\ a,11^3-1=\left(11-1\right)\left(11^2+11+1\right)=10\cdot133=1330\\ b,x^3-y^3=\left(x-y\right)^3+3xy\left(x-y\right)=6^3+3\cdot9\cdot6=378\\ 16,\\ a,M=x^3+27-\left(27-8x^3\right)=9x^3=9\cdot20^3=72000\\ b,N=x^3-8y^3+16y^3=x^3+8y^3=\left(x+2y\right)\left(x^2-2xy+4y^2\right)=0\)
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