帮我解决几道大学高数题lim(x_0)(e^ax -1)/sinbxlim(x-1)(x-1)/(x-π)lim(1-1/x)^根号xlim(x-无穷){(2x+1)/(2x-1 )}^xlim(x-无穷)(1+2^x+3^x)^1/x会几道就帮我解几道吧,

来源:学生作业帮助网 编辑:六六作业网 时间:2024/11/22 04:03:36
帮我解决几道大学高数题lim(x_0)(e^ax-1)/sinbxlim(x-1)(x-1)/(x-π)lim(1-1/x)^根号xlim(x-无穷){(2x+1)/(2x-1)}^xlim(x-无穷

帮我解决几道大学高数题lim(x_0)(e^ax -1)/sinbxlim(x-1)(x-1)/(x-π)lim(1-1/x)^根号xlim(x-无穷){(2x+1)/(2x-1 )}^xlim(x-无穷)(1+2^x+3^x)^1/x会几道就帮我解几道吧,
帮我解决几道大学高数题
lim(x_0)(e^ax -1)/sinbx
lim(x-1)(x-1)/(x-π)
lim(1-1/x)^根号x
lim(x-无穷){(2x+1)/(2x-1 )}^x
lim(x-无穷)(1+2^x+3^x)^1/x
会几道就帮我解几道吧,

帮我解决几道大学高数题lim(x_0)(e^ax -1)/sinbxlim(x-1)(x-1)/(x-π)lim(1-1/x)^根号xlim(x-无穷){(2x+1)/(2x-1 )}^xlim(x-无穷)(1+2^x+3^x)^1/x会几道就帮我解几道吧,
1.lim(x->0) (ax)/(bx) = a/b
2.lim(x->1) (x-1)/(x-π) = 0
3.lim(x->+∞) (1-1/x )^√x = lim(x->+∞) (1-1/x )^x * (1/√x)
lim(x->+∞) (1-1/x )^x = e^(-1) = 1/e,1/√x -> 0
原式 = 1
4.lim(x->∞) [1+ 1/(x+1/2) ] ^ (x+1/2) * [ x /(x+1/2)]
= e^1 = e
5.3^x < 1+2^x+3^x < 3 * 3^x
3 < (1+2^x+3^x)^1/x < 3 ^(1/x) * 3
lim(x->∞) 3 ^(1/x) = 3^0 = 1 由迫敛准则(夹挤准则),得:
lim(x->∞) (1+2^x+3^x)^1/x = 3

利用等价无穷小做代换

a/b