Question

calcule as potencias

a ) -7²

b) (-7)²

c) (-7²)

d ) ( 3 )²
( 5 )

e ) ( 3 )-²
( 5 )

Answer 1

a ) $-7^2 = -(7 \times 7) =-49$

b) $(-7)^2 = (-7) \times (-7)=+49$

c) $(-7^2) = -7^2 = -49$

d ) $\left ( \dfrac{3}{5} \right )^2 = \dfrac{3}{5} \times \dfrac{3}{5} = \dfrac{3 \times 3}{5 \times 5}= \dfrac{9}{25}$

e ) $\left ( \dfrac{3}{5} \right )^{-2} = \dfrac{1}{\left ( \dfrac{3}{5} \right )^{2}} = \dfrac{1}{\dfrac{3}{5} \times \dfrac{3}{5} } = \dfrac{1}{\dfrac{3 \times 3}{5 \times 5}} = \dfrac{1}{\dfrac{9}{25}}=\dfrac{25}{9}$




Bons estudos!