Question

Resolva as adições e subtrações de notação científica:

A) 5x10² + 7x10⁵ =

B) 2x10² + 12x10-¹ (o expoente é –1 menos um) =

C) 3, 987x10⁵ – 9,515x10⁶



Por favor me ajudem!

Answer 1

Precisamos igualar os expoentes

a) $7\times10^5=7000\times10^2$

$5\times10^2+7\times10^5=5\times10^2+7000\times10^2$

$5\times10^2+7\times10^5=(5+7000)\times10^2$

$5\times10^2+7\times10^5=7005\times10^2$

$5\times10^2+7\times10^5=7,005\times10^5$

b) $2\times10^2=2000\times10^{-1}$

$2\times10^2+12\times10^{-1}=2000\times10^{-1}+12\times10^{-1}$

$2\times10^2+12\times10^{-1}=(2000+12)\times10^{-1}$

$2\times10^2+12\times10^{-1}=2012\times10^{-1}$

$2\times10^2+12\times10^{-1}=2,012\times10^{2}$

c) $9,515\times10^6=95,15\times10^5$

$3,987\times5-9,515\times10^6=3,987\times10^5-95,15\times10^5$

$3,987\times5-9,515\times10^6=(3,987-95,15)\times10^5$

$3,987\times5-9,515\times10^6=-91,163\times10^{5}$

$3,987\times5-9,515\times10^6=-9,1163\times10^6$