Question

СРОЧНО!!!
решите пожалуйста
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Answer 1

$1)\;\frac14-x^2+x^4=\left(\frac12\right)^2-2\cdot\frac12\cdot x^2+(x^2)^2=\left(\frac12-x^2\right)^2\\\\\\2)\;y^4-xy^2+\frac14x^2=(y^2)^2-2\cdot y^2\cdot\frac12x+\left(\frac12x\right)^2=\left(y^2-\frac12x\right)^2\\\\\\3)\;\frac9{16}x^2+3xy+4y^2=\left(\frac34x\right)^2+2\cdot\frac34x\cdot2y+(2y)^2=\left(\frac34x+2y\right)^2\\\\\\4)\;\frac94x^2+15xy+25y^2=\left(\frac32x\right)^2+2\cdot\frac32x\cdot5y+(5y)^2=\left(\frac32x+5y\right)^2$