function calcul_art8(){
		var tr_a8 = Number(document.getElementById("trdeprix_a8").value);
			if (tr_a8==1) {
				var p1_a8 = Number(document.getElementById("p1_a8").value);
				var q_a8 = Number(document.getElementById("q_a8").value);
					if (q_a8>=1) {
						var p_a8 = Number(p1_a8);
						var total_a8 = Number(p_a8 * q_a8);
						document.getElementById("total_a8").value = total_a8.toFixed(2);
						var ttc_a8 = Number(total_a8 * 1.196);
						document.getElementById("ttc_a8").value = ttc_a8.toFixed(2);
						}
				}
			else if (tr_a8==2) {
				var s1_a8 = Number(document.getElementById("seuilp1_a8").value);
                var p1_a8 = Number(document.getElementById("p1_a8").value);
				var p2_a8 = Number(document.getElementById("p2_a8").value);
                var q_a8 = Number(document.getElementById("q_a8").value);
					if (q_a8>=0 && q_a8<s1_a8) {
						var p_a8 = Number(p1_a8);
						var total_a8 = Number(p_a8 * q_a8);
						document.getElementById("total_a8").value = total_a8.toFixed(2);
						var ttc_a8 = Number(total_a8 * 1.196);
						document.getElementById("ttc_a8").value = ttc_a8.toFixed(2);
						}
					else {
						var p_a8 = Number(p2_a8);
						var total_a8 = Number(p_a8* q_a8);
						document.getElementById("total_a8").value = total_a8.toFixed(2);
						var ttc_a8 = Number(total_a8 * 1.196);
						document.getElementById("ttc_a8").value = ttc_a8.toFixed(2);
						}
				}
			else if (tr_a8==3) {
				var s1_a8 = Number(document.getElementById("seuilp1_a8").value);
				var s2_a8 = Number(document.getElementById("seuilp2_a8").value);
                var p1_a8 = Number(document.getElementById("p1_a8").value);
				var p2_a8 = Number(document.getElementById("p2_a8").value);
				var p3_a8 = Number(document.getElementById("p3_a8").value);
                var q_a8 = Number(document.getElementById("q_a8").value);
					if (q_a8>=0 && q_a8<s1_a8) {
						var p_a8 = Number(p1_a8);
						var total_a8 = Number(p_a8 * q_a8);
						document.getElementById("total_a8").value = total_a8.toFixed(2);
						var ttc_a8 = Number(total_a8 * 1.196);
						document.getElementById("ttc_a8").value = ttc_a8.toFixed(2);
						}
					else if (q_a8>=s1_a8 && q_a8<s2_a8) {
						var p_a8 = Number(p2_a8);
						var total_a8 = Number(p_a8 * q_a8);
						document.getElementById("total_a8").value = total_a8.toFixed(2);
						var ttc_a8 = Number(total_a8 * 1.196);
						document.getElementById("ttc_a8").value = ttc_a8.toFixed(2);
						}
					else {
						var p_a8 = Number(p3_a8);
						var total_a8 = Number(p_a8 * q_a8);
						document.getElementById("total_a8").value = total_a8.toFixed(2);
						var ttc_a8 = Number(total_a8 * 1.196);
						document.getElementById("ttc_a8").value = ttc_a8.toFixed(2);
						}
				}
    }