console.clear(); let a; console.log(a); a = 15; console.log("Ma variable a = " + a); let b = 9; console.log("Ma variable b = " + b); console.log("15 + 9 = "+ (a+b)); console.log("15 - 9 = "+ (a-b)); console.log("15 * 9 = "+ (a*b)); console.log("15 / 9 = "+ (a/b)); a = "Bonjour"; b = "les amis"; console.log(a +" "+ b); a = true; b = false; console.log("true AND false = "+ (a && b)); console.log("true OR false = "+ (a || b)); a = new Date() console.log(a.toLocaleDateString("ch-FR")); b = new Date(a.getTime() - ((61) * 864000000)); console.log(b.toLocaleDateString("ch-FR")); a = Math.PI; b = "bonjour"; let c = true; let d = new Date(); console.log(a +" est de type "+ (typeof a)); console.log(b +" est de type "+ (typeof b)); console.log(c +" est de type "+ (typeof c)); console.log(d.toLocaleDateString("ch-FR") +" est de type "+ (typeof d));