Question

resolva as equações
a)
${x}^{2} \: \: - 25 = 0$

b)
$2 {x}^{2} - 98 = 0$
c)
$24 = {6}x^{2}$
d)
${64x}^{2} - 1 = 0$
e)
$7{ \times }^{2} - 14 = 0$
f)
$- { \times }^{2} + 49 = 0$
g)
$- 25 + 100 { \times }^{2} = 0$

h)
${ \times }^{2} - \frac{81}{4} = 0$

Answer 1

a) x² - 25 = 0
x² = 25
√x² = √25
x = ±5
S = {5,-5}

b) 2x² - 98 = 0
2x² = 98
x² = 98/2
x² = 49
√x² = √49
x = ±7
S = {7,-7}

c) 24 = 6x²
x² = 24/6
x² = 4
x = ±4
S= {4,-4}

d) 64x² - 1 = 0
64x² = 1
x² = 1/64
√x² = √1/64
x = ±1/8
S = {1/8, -1/8}

e) 7x² - 14 = 0
7x² = 14
x² = 14/7
x² = 2
√x² = √2
x ≈ ±1,41
S= {1,41; -1,41}

f) -x² + 49 = 0 * (-1)
x² - 49 = 0
x² = 49
x = ±7
S= {7,-7}

g) -25 + 100x² = 0
100x² = 25
x² = 25/100
√x² = √25/100
x = ±5/10
S= {5/10, -5/10}

h) x² - 81/4 = 0
x² = 81/4
x = ±9/2
S= {9/2, -9/2}

Bons estudos! :)