Ufyukyu

up vote 0 down vote favorite I am making a PWA with Preact (a React-Native alternative) I am having issues with centering a dropdown. Don't mind the this.animate, that's for preact-motion to trigger an animation on the dropdown. Is there something I am missing here? My goal is for the dropdown to appear centered just below the plus button when the button is pressed. HTML: <div class={style.home}> <div class={style.addSound}> <button class={style.addItem} onClick={this.animate}> <Icon class={styles.selectIcon} src={Plus} /> </button> </div> {/*Passes current value of this.state.height as height value*/} <Motion style={{ height: spring(this.state.height) }}> ...

up vote 1 down vote favorite In a worked example in my textbook, we are describing the cosets in $R/A$ , where $R=mathbb{Z}[i]$ , the Gaussian integers, and $A = (2+i)R$ , the ideal of all multiples of $2 + i$ . It starts by stating that a typical coset $x$ in $R/A$ will have the form $x=(m + ni) + A$ , with integers $m,n$ . This makes sense to me, but I do not understand the following part: "Since $2 + i in A$ , we have $i + A = -2 + A$ " Can someone walk me through how we arrive at $i+A = -2+A$ ? abstract-algebra ring-theory gaussian-integers share | cite | improve this question asked 22 hours ago CurioDidact ...