`d)D=1/2sqrt{a^10b^8}`
`=1/2sqrt{(a^5b^4)^2}`
`=1/2|a^5b^4|`
`=1/2b^4|a^5|`
`a>=0=>D=1/2b^4a^5`
`a<=0=>D=-1/2b^4a^5`
`e)sqrt{(2-sqrt3)^2}+sqrt2`
`=2-sqrt3+sqrt2``
`f)3sqrt5-sqrt{(1-sqrt5)^2}`
`=3sqrt5-(sqrt5-1)`
`=2sqrt5+1`
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\(a.-\dfrac{1}{2}\sqrt{a^{10}.b^8}=-\dfrac{1}{2}a^5b^4\)
\(b.\sqrt{\left(\sqrt{2}-\sqrt{3}\right)^2}+\sqrt{2}\\=\sqrt{3}-\sqrt{2}+\sqrt{2}\\ =\sqrt{3}\)
\(c.3\sqrt{5}-\sqrt{\left(1-\sqrt{5}\right)^2}\\ =3\sqrt{5}-\sqrt{5}+1\\ =2\sqrt{5}+1\)
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