若x的2n次方等于5_求-搜答案-百度作业网

108,谢谢

x^m=5x^n=6x^(3m+2n)=x^3m*x^2n=(x^m)^3*(x^n)^2=(5^3)*(6^2)=4500

x的3m-2n次方等于x的m次方的三次方除以x的n次方的二次方,即为：3^3/(6^2)=3/4

x^(6n)+y^(4n)=[x^(3n)]^2+[y^(2n)]^2=5×5+4×4=25+16=41

(2x^4n)^2-4(x^3)^2n=4x^8n-4x^6n=(x^2n)^4*4-(x^2n)^3*4=5^4*4-5^3*4=625*4-125*4=4*(625-125)=4*500=2000

（xy）2N=x2n·y2n∵xn=5,yn=3,∴x2n=25,y2n=9∴(xy)2N=25·9=225加油学习数学哦~再问：我还要问道题再答：嗯，本人自信数学很好~~哈哈再问：哦*--

由x^(4m+n)÷x^(3m-n)=x^5有4m+n-3m+n=5m+2n=5.∴2m+4n-8=2（m+2n）-8=2×5-8=2.

19的n次方=3的2次方的n次方=3的2n次方题目没错?已知10的m次方等于20,10的n次方等于1/5,求9的m次方除以3的2n次方答案：81再问：抱歉，是我弄错了，应该是：若10的m次方等于20,

x^m=bx^n=b都等于b?应该是x^m=a则x^(3m-2n)=x^3m÷x^2n=(x^m)^3÷(x^n)^2=a^3/b^2

X^(2n)=5[2X^(3n)]^2-3[x^n]^4=4x^(6n)-3x^(4n)=4[x^(2n)]^3-3[x^(2n)]^2=4×5^3-3×5^2=4×125-3×25=500-75=4

x^m=5,x^n=2x^(2m+3n)=x^(2m)*x^(3n)=(x^m)^2*(x^n)^3=5^2*2^3=25*8=200

(XY)^2N=[(XY)^N]^2=[(X^N)(Y^N)]^2=(5x3)^2=15^2=225

x^m=2x^n=5x^(m+n)=x^m*x^n=2*5=10x^(m-n)=x^m/x^n=2/5x^(3m-2n)=x^(3m)/x^(2n)=(x^m)^3/(x^n)^2=2^3/5^2=8

由题意得X的m+2n+1=X的8次方又∵m=2n+1∴X的m+m=X的8次方X的2m=X的8次方∴2m=8m=4∴4=2n+1∴n=3／2mn=4×3／2=6希望满意采纳,祝学习进步.

x的m+k+3n次方等于x的m次方×x的k次方×（x的n次方）³=9×4×2²=288

x^(6n)+x^(4n)*x^(5n)=x^(6n)+x^(9n)=[x^(3n)]^2+[x^(3n)]^3=2^2+2^3=4+8=12

解由已知得原式=x^6m+y^3n-x^6m*y^3n=16+5-16*5=-59同底数幂相乘,底数不变,指数相加即：a^m×a^n＝a^(m+n)（a^m）^n=a^mn（这个忘了咋说的了.）

即2x(2+m)y^2+6x^3y^4=2x^5y^2-6x^3y^n所以2+m=5,4=n则m=3,n=4

20的n次方5^n=24^n=320^n=(4*5)^n=4^n*5^n=2*3=6