Thực hiện phép tính sau
a) (x + 3)\(^2\) b) (2x + 3).(x\(^2\) - 2x + 3) c) (30x\(^4\)y\(^3\) - 25x\(^2\)y\(^3\) - 3x\(^4\)y\(^4\)) : (5x\(^2\)y\(^3\))
d) (x - 5).(2x + 1) - 2x(x - 3) e) (2 + 3x).(2 - 3x) + (3x + 4)\(^2\)
f) (3 - 2a)\(^2\) g) (10x\(^3\)y - 5x\(^2\)y + 15xy\(^2\)) : (5xy) h) (4x - 1).(x\(^2\) - x +5)
d: \(\left(x-5\right)\left(2x+1\right)-2x\left(x-3\right)\)
\(=2x^2+x-10x-5-2x^2+6x\)
=-3x-5
e: \(\left(2+3x\right)\left(2-3x\right)+\left(3x+4\right)^2\)
\(=2^2-\left(3x\right)^2+9x^2+24x+16\)
=4+24x+16=24x+20
f: \(\left(3-2a\right)^2=\left(2a-3\right)^2=\left(2a\right)^2-2\cdot2a\cdot3+3^2\)
\(=4a^2-12a+9\)
g: \(\dfrac{10x^3y-5x^2y+15xy^2}{5xy}=\dfrac{5xy\cdot2x^2-5xy\cdot x+5xy\cdot3y}{5xy}\)
\(=\dfrac{5xy\left(2x^2-x+3y\right)}{5xy}=2x^2-x+3y\)
h: \(\left(4x-1\right)\cdot\left(x^2-x+5\right)\)
\(=4x^3-4x^2+20x-x^2+x-5\)
\(=4x^3-5x^2+21x-5\)
a: \(\left(x+3\right)^2=x^2+2\cdot x\cdot3+3^2\)
\(=x^2+6x+9\)
b: \(\left(2x+3\right)\left(x^2-2x+3\right)\)
\(=2x^3-4x^2+6x+3x^2-6x+9\)
\(=2x^3-x^2+9\)
c: \(\dfrac{30x^4y^3-25x^2y^3-3x^4y^4}{5x^2y^3}\)
\(=\dfrac{5x^2y^3\left(6x^2-5-\dfrac{3}{5}x^2y\right)}{5x^2y^3}\)
\(=6x^2-5-\dfrac{3}{5}x^2y\)
