Найдите сумму первых сорока членов арифметической прогрессии (an): -42,5 ; -40. Created by sophiabannova. algebra-ru

Найдите сумму первых сорока членов арифметической прогрессии (an): -42,5 ; -40...

sophiabannova @sophiabannova

July 2022 1 10 Report

Найдите сумму первых сорока членов арифметической прогрессии (an): -42,5 ; -40

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$a_{1}=-42,5\\ a_{2}=-40\\\\ a_{2}= a_{1} +d\\\\d= a_{2} - a_{1}=-40-(-42,5)=-40+42,5=2,5 \\\\ a_{40}= a_{1} +39d=-42,5+39*2,5=-42,5+97,5=55\\\\ S_{40} = \frac{ a_{1} + a_{40} }{2} *40=(-42,5+55)*20=12,5*20=250$

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kakuyu chast razvyornutogo ugla sostavlyaet ugolgradusnaya mera kotorogo ravna19

karandash stoit 15 r kakoe naibolshee kolichestvo karandashej mozhno kupit imeya 2

sintaksicheskij razbor pozhalujsta 24 pred

najdite koren uravneniya x 10x30 x 20x20 40

ch kakoe rasstoyanie budet mezhdu nimi cherez 6 ch posle nachala dvizheniyacae191f06ee657d9ee0f42f6c836eb82 87974

najdite v tekste slova v perenosnom znachenii vse leto listya podstavlyali solncu

ch bolshechem skorost drugogokakoe rasstoyanie budet mezhdu nimi cherez 7 ch posle00474c71ae1e5c7d414f4f1f446466f7 62488

umolyayu pomogite pushkin dubrovskij sushestvovalo li v dejstvitelnosti soglas

pushkin dubrovskij chem pohozhi i chem otlichayutsya dva soseda pomeshika

o kakom yavlenii prirody fityutchev pisaloprometchivo bezumno vdrug na dubravu na

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