Toán so sánh:a. 27^25 và 32^15 b.2^84 và 5^35 07/09/2021 By Claire so sánh:a. 27^25 và 32^15 b.2^84 và 5^35
a.Ta có:$27^{25}$ =$(3^{3}) ^{25}$ =$3^{3.25}$ =$3^{75}$ . $32^{15}$ =$(2^{5}) ^{15}$ =$2^{5.15}$ =$2^{75}$ . Vì $2^{75}$ <$3^{75}$ ⇒$32^{15}$ <$27^{25}$ . b.Ta có:$2^{84}$ =$2^{12.7}$ =$(2^{12} )^{7}$ =$4096^{7}$ $5^{35}$ =$5^{5.7}$ =$(5^{5}) ^{7}$ =$3125^{7}$ . Vì $3125^{7}$ <$4096^{7}$ ⇒$5^{35}$ <$2^{84}$ . Trả lời
Đáp án: a, $27^{25}$ = ($3^{3}$)$^{25}$ = $3^{75}$ $32^{15}$ = ($2^{5}$)$^{15}$ = $2^{75}$ Do $3^{75}$ > $2^{75}$ ⇒ $27^{25}$ > $32^{15}$ b, $2^{84}$ = ($2^{12}$)$^{7}$ = $4096^{7}$ $5^{35}$ = ($5^{5}$)$^{7}$ = $3125^{7}$ Do $4096^{7}$ > $3125^{7}$ ⇒$2^{84}$ > $5^{35}$ Trả lời
a.Ta có:$27^{25}$ =$(3^{3}) ^{25}$ =$3^{3.25}$ =$3^{75}$ .
$32^{15}$ =$(2^{5}) ^{15}$ =$2^{5.15}$ =$2^{75}$ .
Vì $2^{75}$ <$3^{75}$ ⇒$32^{15}$ <$27^{25}$ .
b.Ta có:$2^{84}$ =$2^{12.7}$ =$(2^{12} )^{7}$ =$4096^{7}$
$5^{35}$ =$5^{5.7}$ =$(5^{5}) ^{7}$ =$3125^{7}$ .
Vì $3125^{7}$ <$4096^{7}$ ⇒$5^{35}$ <$2^{84}$ .
Đáp án:
a, $27^{25}$ = ($3^{3}$)$^{25}$ = $3^{75}$
$32^{15}$ = ($2^{5}$)$^{15}$ = $2^{75}$
Do $3^{75}$ > $2^{75}$
⇒ $27^{25}$ > $32^{15}$
b, $2^{84}$ = ($2^{12}$)$^{7}$ = $4096^{7}$
$5^{35}$ = ($5^{5}$)$^{7}$ = $3125^{7}$
Do $4096^{7}$ > $3125^{7}$
⇒$2^{84}$ > $5^{35}$